Each slice of this easy egg breakfast casserole is thick, flavorful, and satisfying; plus, the recipe is an incredibly convenient breakfast choice since it’s make-ahead and infinitely adaptable. Like quiche and breakfast egg muffins, you can use your favorite seasonings and cheeses, vegetables like peppers and mushrooms, meats like sausage or bacon, or you can make it vegetarian. The best part is that you can assemble this dish ahead of time so breakfast is a breeze in the morning!
I originally published this recipe in 2015 and have since added new photos, a video tutorial, and more helpful success tips. I’ve also simplified the recipe instructions.
Breakfast casserole is an all-in-one hearty meal that can be made ahead of time, feeds a crowd, reheats well, and makes great leftovers. My family devours it. For all these reasons and more, I’ve made it nearly 100x (no exaggeration there) for breakfast, brunch, and, yes, dinner. It’s one of my favorite Easter brunch recipes to serve each year, too.
Let me show you how it comes together so you too can experience this crowd-pleasing superhero meal.
One reader, Mary, commented: “Love it! It is literally the perfect recipe. I’ve made it a few times now and everyone loves it, including my in-laws. We’ve made it for a crowd and also done it for the week as a meal prep for my husband and I. We love that it’s all in one (protein, veggies, carbs, etc.), easy to make, and can be made ahead. I cannot recommend this recipe enough! ★★★★★“
This Easy Breakfast Casserole Is:
- Adaptable to whatever vegetables, meats, cheeses, and herbs you have on hand.
- Easy to make ahead of time.
- Quick to throw together.
- Great as a quick weekday meal or a lavish weekend or holiday brunch.
- Excellent for entertaining a crowd.
- Made with some bread to soak up moisture, but potatoes work too!
- Ready for your favorite egg toppings like salsa, pico de gallo, green onion, cilantro, parsley, avocado, everything bagel seasoning, hot sauce, etc.
4 Main Components
When gathering ingredients for this recipe, I like to think of it as having 4 separate components. From there, you can have fun with variations.
- Vegetables
- Meat (or extra vegetables)
- Starch for soaking up moisture
- Egg, cheese, & milk mixture
Here Are the Endless Add-ins & Flavor Options
- Vegetables: Select which vegetables you’d like in the dish. Generally, the most popular with guests is bell peppers, spinach, and mushrooms. But I’ve also made this with broccoli/peppers, kale/mushrooms, and spinach/zucchini. Try to stick to 3–4 cups of vegetables total. Cook the vegetables down with some flavor-enhancing onion and garlic.
- Meat: Guests usually prefer meat in the casserole, so I add sausage. Or try using ground turkey, chopped bacon, ground beef, or ground chicken. I usually purchase uncooked sausage for this and brown it with some dried rosemary or Italian seasoning to give it a little extra flavor, but that is optional. If the meat you’re using is pre-cooked, such as chopped ham or shredded chicken, you can mix it with the cooked vegetable mixture before layering it into the dish.
- Starch: Like when making sausage & herb stuffing, breakfast strata, and French toast casserole, the bread should be slightly stale so it can soak up moisture. Crusty sourdough or homemade ciabatta bread are FANTASTIC here. You can also use homemade artisan bread, seeded oat bread, whole wheat bread, a loaf of French bread, crusty baguette, biscuits, bagels or homemade bagels, or even day-old croissants (have you tried homemade croissants?!). To make it gluten free, use gluten-free bread or potatoes.
- Eggs, milk, & cheese: Whisk a dozen eggs with a little half-and-half or milk and stir in some shredded cheese. Like the vegetables and meat, use whatever cheeses you like best, such as sharp cheddar, pepper jack, feta, and/or smoked gouda.
Variations: One of my favorite variations of this recipe is everything bagel breakfast casserole. It’s a BIG HIT and consistently gets rave reviews. Or try my different method/recipe for biscuit breakfast casserole with homemade biscuits baked right on top.
Can I Use Potatoes?
Yes, you can replace the bread with diced hash brown potatoes—the kind you find in the freezer section of the grocery store. Guests have *loved* this version. Use about 3 cups (around 380g) of hash browns in place of the bread. You could also peel and dice fresh potatoes, but you’ll need to quickly cook them on the skillet for 10 minutes before using in this dish.
Another wonderful make ahead option with fresh potatoes is this ham and potato casserole that is egg free, but just as delicious.
Do I Have to Use Bread?
Bread or potatoes, yes. Besides eggs, bread is the main ingredient. To avoid a spongey, wet dish, this breakfast casserole needs structure at the bottom. You see, when eggs bake, they release a lot of liquid. Chunks of crusty bread (or hash brown potatoes) soak up some liquid so the casserole is chunky and textured, not flat and wet. It’s almost like the way we need an English muffin with our eggs benedict—to help soak up all that eggy goodness.
If you’re looking for something without this starchy addition, crustless vegetable quiche or an easy frittata are great options.
In Pictures: How to Make Breakfast Casserole
First, place the pieces of bread (or potatoes) in the bottom of a greased 9×13-inch or any 3–4-quart oven-safe dish. I usually use (affiliate links) this glass pan or the pictured red ruffled baking dish, which comes in a set with other sizes—definitely a splurge, but I’ve found the quality to be excellent. Showing you the bread scattered in the pan as well as the optional potato substitution:
Set that aside and pre-cook your vegetables and meat (if the meat is not cooked already). You can do this all in 1 big skillet on the stove, adding onion, garlic, and optional herbs like dried rosemary or your favorite seasoning blend. As that’s sizzling on the stove, whisk the eggs, milk, and cheese together:
Now it’s time to assemble, and I’ve made this process a lot easier over the years. Spoon all of the vegetables/meat mixture on top of the bread. Pour the egg mixture all over that:
Success Tip: Refrigerate Overnight
At this point, you can either bake it right away or refrigerate the casserole overnight and for up to 24 hours. During this time, the flavors mingle together and the bread has a chance to soak up some of the liquid and flavor. Wake up and all you have to do is slide it into the oven. If you’re in a rush, I do recommend at least 30 minutes in the refrigerator before baking, if you can spare it!
Bake until the edges are golden brown. Because it’s so egg heavy, the casserole puffs up in the oven like a cheesecake and then sinks back down as it cools. Cool for 5–10 minutes before slicing and serving.
What to Serve With Breakfast Casserole
For side dishes, fresh fruit and yogurt are light, simple, and quick. For healthy recipe ideas, see my complete list of 30+ healthy breakfast recipes. However, if you’re entertaining—or if you have several hungry teenagers in your house— you’ll love pairing this breakfast casserole with:
- Easy Cinnamon Rolls
- Slow Cooker Cinnamon Rolls
- Maple Chicken Breakfast Sausage
- Pumpkin Cinnamon Rolls or Pumpkin Crumb Cake
- Banana Muffins or Blueberry Muffins
- Baked Oatmeal
- Sour Cream Coffee Cake
- Banana Bread or Zucchini Bread
- Apple Cider French Toast
- Dark Chocolate Raspberry Coffee Cake, a Cinnamon Roll Wreath, or Cranberry Cake (great options around the holidays)
- A Dutch baby piled high with your favorite sweet toppings
- Or any other of my make ahead breakfast ideas!
Your brunch guests will be beyond satisfied. Yes, even the teenagers!
Print
Easy Make-Ahead Breakfast Casserole
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour, 30 minutes
- Yield: serves 12
- Category: Breakfast
- Method: Cooking
- Cuisine: American
Description
This easy breakfast casserole is infinitely adaptable and you can find variations and suggestions in the recipe Notes below. The version written below with sausage, mushrooms, bell peppers, spinach, and cheddar cheese is generally the most popular with guests. You can assemble the entire dish and refrigerate for up to 24 hours before baking.
Ingredients
- 4 cups (175g or 6 oz) cubes of crusty bread*
- 1 teaspoon olive oil
- 1 pound ground pork sausage, casings removed*
- 1 teaspoon dried rosemary or Italian seasoning, optional
- 3/4 cup (100g) chopped yellow onion (1/2 of a large onion)
- 2 garlic cloves, minced
- 2 cups (275g or 9–10 oz) chopped bell peppers
- 1 cup (100g or 3 oz) sliced mushrooms
- 1 cup roughly chopped fresh spinach
- 12 large eggs
- 1/4 teaspoon salt
- 1/8 teaspoon freshly ground black pepper
- 2/3 cup (160ml) milk or half-and-half*
- 1 cup (100g or 3.5 oz.) shredded cheddar cheese
- optional garnish: green onion and/or chopped parsley
Instructions
- Grease a 9×13-inch or any 3–4-quart oven-safe dish. Arrange bread cubes in an even layer in bottom of pan.
- Heat olive oil in a large skillet over medium heat. Add sausage and rosemary/Italian seasoning, if using, and break up the sausage into bite-size pieces with a wooden spoon or rubber spatula as it begins to cook. Add the onion, garlic, peppers, mushrooms, and spinach and cook until everything has slightly softened and sausage is mostly cooked through, about 5–6 minutes.
- Remove sausage and vegetable mixture from heat and spread in an even layer on top of bread.
- Whisk the eggs, salt, pepper, milk, and cheese together. Evenly pour over sausage/vegetable mixture. Add another sprinkle of salt and pepper on top.
- Cover casserole with plastic wrap or aluminum foil and refrigerate for at least 30 minutes and up to 24 hours. (When ready to bake, allow to sit at room temperature for 10–15 minutes as oven preheats.)
- Preheat the oven to 375°F (191°C). Bake the casserole, uncovered, until the top is golden, edges are crisp, and a toothpick inserted in the center comes out clean, about 40–45 minutes.
- Cool for 10 minutes, then slice and serve.
- Leftovers keep well in the refrigerator for up to 5 days. Reheat in the microwave to your liking.
Notes
- Make Ahead Instructions: This is an excellent make-ahead recipe because you can assemble it before baking up to 24 hours in advance. See step 5. You can also cook the sausage and vegetable mixture up to 24 hours in advance, cover and refrigerate until ready to use.
- Freezing & Reheating Instructions: To freeze, prepare and assemble through step 5, cover with plastic wrap, then a layer of aluminum foil, and freeze for up to 3 months. Thaw overnight in the refrigerator, and then bring to room temperature before baking as directed. You can also freeze the baked casserole for up to 3 months and when doing that, I suggest baking it in a disposable aluminum pan. Cool completely, cover with plastic wrap, then a layer of aluminum foil. When ready to eat, thaw it for about 24 hours (covered) in the refrigerator, remove the plastic wrap layer, then bake in a 350°F (177°C) oven for 25–30 minutes.
- Special Tools (affiliate links): 9×13-inch Baking Dish or any 3–4-quart Oven-Safe Dish | Glass Mixing Bowls | Whisk
- Bread: Crusty sourdough is fantastic in this recipe, or use any crusty, hearty bread. The crustier or more stale, the better. If your bread is fresh and/or flimsy, cut into cubes and bake on a baking sheet in a 300°F (149°C) oven for 10 minutes. It’ll be slightly crisp and ready to use in this recipe. No need to wait for the bread to cool before layering into the baking dish.
- Using Potatoes Instead of Bread: You can replace the bread with diced hash brown potatoes—the kind you find in the freezer section of the grocery store. Use about 3 cups (around 380g) of frozen hash brown potatoes, no need to thaw. You could also peel and dice fresh potatoes, but you’ll need to quickly cook/brown them on a skillet with 1 Tablespoon olive oil over medium heat for 10 minutes before using.
- Sausage or Other Meat: If using pre-cooked sausage links or ham, cut into slices/chunks, and there is no need to cook either. Simply stir into the pre-cooked vegetables before layering into the dish. You can replace the sausage with ground turkey, beef, or chicken—simply pre-cook with the vegetables according to the instructions. If using bacon, I recommend reducing to 1/2 pound and cutting into bite-size pieces. Cook separately from the vegetables until browned. Drain, then mix with the vegetables before layering into the dish.
- Other Vegetables: Feel free to replace all or some of the bell peppers, mushrooms, and spinach with other vegetables such as chopped broccoli, sliced zucchini or squash, or kale. Pre-cook as directed.
- Vegetarian Option: You can leave out the meat and replace with another 1 cup of vegetables.
- Milk: For the richest, heartiest texture, I recommend half-and-half or whole milk. You can use lower-fat milk or dairy-free milk if desired.
- Cheese: I usually use a blend of regular and sharp white cheddar cheeses. Use whatever cheeses you like best, such as pepper jack, feta cheese, Swiss, and/or smoked gouda.
- Half Recipe: You can halve this recipe by halving all of the ingredients and using a 9×9-inch square pan. Bake time is slightly shorter, about 32–36 minutes.
Nutrition
- Serving Size:
- Calories: 212
- Sugar: 3.1 g
- Sodium: 343 mg
- Fat: 12.8 g
- Carbohydrates: 11.2 g
- Protein: 12.5 g
- Cholesterol: 205.4 mg
Reader Comments and Reviews
I’m thinking of making this but am looking for something I can just grab and eat on the go. So, if I cut the squares a bit smaller can this be something eaten with fingers or must a fork be used?
Hi Susan, this may be a little soft to eat with your hands, but we love these egg muffins – great for a grab and go breakfast.
Thank you!
I attempted to make this but even after 45 mins of baking, the egg mixture didn’t seem to cook that well.
What setting on the oven should I have used? Fan-forced? I just used the simple bake
Hi Mona, what type of bread did you use? A soft bread will result in a casserole that does not set as well. We always recommend conventional settings for baking (not convection/fan). The flow of air from convection heat can cause baked goods to rise and bake unevenly and it also pulls moisture out of the oven. If you do use convection/fan settings for baking, lower your temperature by 25 degrees F and keep in mind that things may still take less time to bake.
Are you using diced hash browns that are frozen? Or thawed? Or uncooked? Thanks! I’m excited to try this out
Hi Claire! You can use frozen hash browns – no need to thaw before using. Hope it’s a hit!
We did not like this at all. Too sense. I was concerned while making the recipe due to the little amount of milk or half & half it called for the texture would not be light and fluffy like many other egg dishes I’ve made. I think it needs double the liquid and a much lower oven temperature. 325 F would have been ideal. It’s also very bland. I agree with the other reviewers, it needs more salt. I would never make this again.
I made this for my mother’s Saturday morning prayer brunch at her church. I prepared everything the night prior, let it sit overnight, and then baked it that Saturday morning, which is actually this Saturday morning.
Instead of using bread, I used diced potatoes. And because I only had green bell peppers and not red, in addition to using those green bell peppers, I added fresh Roma tomatoes. However, I did not include those tomatoes in the mixture that goes on top of the potatoes. I placed my potatoes, and then I placed my mixture and then I scattered the tomatoes around. I did not want them to be overcooked since I was baking everything the next morning.
The best part about this is I had enough left over to make a mini casserole for myself the next morning lol.
This recipe is super tasty and I look forward to trying out more of your recipes!
Can you use stuffing cubes
Hi Kelli, that would depend on how big they are, but they should work!
I did use 4 cups of seasoned stuffing mix (not Stove Top mix) and it came out really good.
This is amazing! I was looking for the answer to this exact question. LOL I just made it with the stuffing cubes since that’s what I have on hand. I’ll let you know how it goes after brunch tomorrow. 🙂
Stuffing cubes were a success! I used those instead of the bread and extra baby portobello mushrooms instead of the sausage. Everyone in my book club loved it!
Made this for Easter. I added approximately 1/2# of chopped bacon and a can of diced green chiles, drained. All other ingredients were per the recipe. It turned out quite dense. Any thoughts on why?
Hi Penny, the egg mixture will bind all of the ingredients together when baking to keep them together, but we wouldn’t necessarily call that dense. Was the breakfast casserole dry? Did you add any extra bread or potatoes? Is it possible your oven runs a little hot? We always recommend an oven thermometer so ensure it’s baking at the correct temperature. Thanks for giving this recipe a try!
I carefully measured 4 cups of cubed bread. The casserole was a bit dry and had kind of an egg layer at the bottom. My oven runs cooler, although 40 minutes was perfect. The flavor was great. Thanks for your feedback.
I put casserole together last night and baked this morning. My brunch guests loved it. I ended up using 1/3 cup buttermilk and 1/3 cup low-fat milk. I ommited peppers (personal preference) and used Italian bread from grocery bakery. I can see how this casserole could be versatile using varied ingredients. Look forward to finding sourdough bread to use next time.
Can I substitute use 1/3c buttermilk and 1/3 cup lowfat milk in recipe?
Hi Veronica, that should be okay.
Can I use Italian sausage?
Hi Joni, yes, absolutely! Cooked Italian sausage would work great here.
Made this for a brunch and it was really, really good. I used ground turkey and did the diced hash potatoes as suggested. It is SO convenient that you can make this ahead of time and then pop it into the oven when you’re ready. Will def make again.
I just made this yesterday for today’s brunch. No sourdough to be had, so I used Italian semolina bread. No meat b/c I am vegetarian; no cheese b/c I am lactose intolerant. Used onions, bell pepper, mushrooms, and spinach; used oat milk with the eggs instead of cow’s milk. It all worked and was a big hit. Even my highly skeptical husband loved it. Thanks for posting this recipe!
I’ve never been a fan of breakfast casseroles but thought I’d try this recipe. My daughter leaves early in the morning for work and doesn’t have to make breakfast. I followed the recipe pretty closely and used most of a loaf of homemade sour dough bread (cubed and dried in the oven), turkey sausage, and hand-grated medium white cheddar cheese. It’s not too cheesy, and the bread makes a great texture. This recipe is a keeper!
I have made this recipe in the past and it is ALWAYS a huge crowd pleaser. I have been asked if Egg beaters/egg whites can be substituted for eggs?
Hi Lori, we haven’t tested this recipe with only egg whites. We’re unsure of the exact amount that would be best – let us know if you try it!
#1. Can I serve this Easy Make-Ahead Breakfst Casserole, with a side dish of my home-made Brioche bread french toast (on which I put fresh strawberries and blueberries, with maple syrup?
#2. If I can do #1 (french toast), would I also need bagels or some type of bread to accompany this casserole? or would that be too much bread ????
Hi Sandra, certainly. We don’t think an additional bread would be necessary, but it wouldn’t hurt to have another option!
Can I make this recipe and freeze? Thank you
Sure can. See the recipe notes for details.
Another great recipe!! I made this for a event at church and everyone loved it! The only thing I did differently was add some extra cheese on top before it baked. Thank you!
Very yummy and easily customizable. Thank you!
Even my picky eaters liked this. I made a few easy changes as to what I had on hand and added canned mushrooms later to only half.
I will definitely make it the night before next time.
This was a good recipe and easy to make. I followed the recipe to the letter but we found the salt lacking. When I make this again, I will increase the amount of salt.
This is just the thing I’ve been looking for!! Thank you for sharing this recipe. Random question, as I can’t eat bread of potatoes, and I’m trying to make something for my breakfasts before work that isn’t just a block of cooked egg…. do you think, instead of bread or potato, I could use a grain mixed in to soak up moisture, like brown rice, quinoa or rolled oats? A bit strange, sure, but maybe it could work?? Thoughts?
I wouldn’t use oats, but you can certainly try rice or quinoa. I haven’t tested it to be certain, so let me know what you try!
I use left over pasta (typically spaghetti) and make more if a “fritatta”. My husband prefers it over a bread-y breakfast bakes. Funny thing is, no one is ever aware there is pasta in there unless you tell them. Hope this helps.
I made this for dinner tonight and it was delicious. I used what I had on hand, which included parmesan instead of cheddar, bacon instead of sausage, and green onions instead of regular onions. I also added tomatoes. I almost always have sourdough on hand so that was easy and made for a nice crust.
We had this recipe on Christmas morning and it was a hit! The bread added light volume without being soggy, the vegetables were fresh and perfectly cooked, and the sausage added a boost of protein that gave us all the energy to open our presents. I have made this once more since and found that it is a delightful make-up breakfast option that only requires a quick 2 minutes in the microwave. I think I will keep trying different versions of this recipe such as substituting potatoes or trying different vegetables since it is just so easy and delicious. Thanks for sharing!
If I’m using frozen diced hashbrowns, but making 24 hours ahead of time do I wait and add frozen potatoes right before baking the next morning?
Hi Devyn, you can assemble the entire dish (including the frozen potatoes). Enjoy!
Eggcellent with frozen hash browns, spinach, onion, mushroom!
This was the perfect crowd pleaser for Christmas morning! Everyone went back for seconds. I was curious if you or anyone has tried freezing the baked version in single servings for an easy breakfast grab? Hoping for some reheat insights.
Hi Lauren! We’re sure you could, but we haven’t tested it with this recipe. We’re sure it would be similar to freezing and reheating our egg muffins recipe – see recipe Notes there.
Can you fully bake this the evening before? What would the reheating instructions be?
I’m looking for an egg bake to bring to an Easter brunch potluck. There’s not enough time to bake it there since everyone wants to eat asap after church ends.
Hi KC, you can reheat the baked casserole by baking in a 350°F (177°C) oven for about 25–30 minutes. Hope it’s a hit!
I really liked the recipe!! It was still very good after leaving it in the fridge for 48 hours before baking:)
Sally, Fantastic recipe! Made this for our Christmas Brunch and it was such a hit. Will be making again and again for our friends & family – so perfect for larger gatherings. Thank you so much ❤️
Same here! Made two for our brunch crowd and everyone loved it. This morning my husband mentioned we should make it again soon–maybe for New Year’s!
This was a hit. I used the diced frozen potatoes and subbed the veggies to what my family likes. I also ended up splitting it into two and using 2 8×8 glass dishes and letting them sit in the fridge for about 30 min before. I will make this again.
My family loved this! We were a bit hesitant to try the recipe after a plethora of underwhelming and overly rich Thanksgiving casseroles, but this was just right. The vegetables even made us feel slightly healthier m!
This was absolutely terrible. Followed the recipe to a T. Used homemade sourdough. Homesteader and tremendous cook! Disappointing on Christmas morning…
Hi. I bought frozen hash browns that are the shredded variety rather than diced. Would this still work as an appropriate substitute for the bread? I planned on making it 24hrs in advance.
Thanks for your help!
Hi Jennifer, several readers have reported success using shredded hash browns. Let us know how it turns out for you!
I just prepared the dish and was wondering if it’s ok to keep it in the fridge for 48 hours instead of 24 hours before baking?
Hi Anne, I’m sure that would be fine, but I fear the bread will soak up too much moisture, and remain a bit soggy in the baked casserole.