Unbelievable Blueberry French Toast Casserole.
There’s not one word more perfect than “unbelievable” to describe this overnight blueberry french toast casserole. Perfect make-ahead recipe for busy mornings!
Now THIS is french toast! Made with chunks of crusty bread, sweet blueberries, lots of brown sugar, a sweet egg-y custard, assembled in a baking pan, and topped with brown sugar cinnamon streusel.
There’s enough goodness to make your entire family happy. And then some.
This casserole is the definition of comfort food. I made it for my friends Kristin and Chris who just welcomed baby girl Keira Elizabeth to the world. Guess I should’ve used strawberries, huh? Oh well. I prepped the french toast the night before and brought the dish to them the next morning after baking it for about 45 minutes. That’s the beauty of this breakfast… it’s designed to be made ahead of time.
It’s designed to MAKE LIFE EASIER!
I typically use challah bread when I make french toast– either in traditional form or as a casserole. You can use sourdough bread or french bread too. Homemade or store-bought, whichever is easiest. Even homemade honey-oat bread would be fantastic. No matter what type of bread you use– make sure it’s crusty. Day-old and a little stale. Bread that’s been sitting out a day or two (and therefore has lost some moisture) will absorb much more of the egg custard.
Speaking of the egg custard. What you’ll make is a thick mixture of eggs, milk, brown sugar, vanilla, and cinnamon. 1/2 teaspoon of cinnamon will go into the custard AND in the streusel on top. The cinnamon soaking into the bread is phenomenal!
For that creamy custard taste, I use 8 eggs total and a little over 2 cups of whole milk. Whole milk is key; I don’t suggest a lower fat milk. Even half-and-half would do. You want a luxurious, thick custard. As always, I use Eggland’s Best eggs here. Not only am I an official brand ambassador of this well respected company, I’m also a huge fan of the quality and taste of their eggs. Always have been!
You’ll cut the bread up into cubes, pour the custard overtop, and stick the whole pan in the refrigerator. During this time, the crusty bread soaks up the cinnamon spiced egg custard, imparting flavor and moisture into the dish as a whole. You can leave it in the refrigerator anywhere from overnight down to 3-4 hours. I find the longer the bread soaks, the tastier the casserole. So, put the refrigerator to work!
During the last few minutes of fridge-time, prepare a brown sugar streusel topping. This is like icing on the cake. The streusel topping is made from equal parts brown sugar and flour, a dose of cinnamon, and cold butter. Emphasis on the cold! The butter is cut into the other 3 ingredients using a pastry blender. Alternatively, you can use two forks or even your fingers.
Sprinkle it over the soaked bread and bake until golden brown. This is the kind of breakfast you make on the weekend not only to gobble up with friends and family, but to smell it as it bakes. I always thought baking banana bread was the best aroma from the oven but this… oh man. It’s even better.
There’s so much texture and flavor, but I think the best part of this overnight french toast is the juicy blueberries. They pop and burst, leaving sweet blueberry juice in between all the cracks and crevices of the casserole.
Fill your plate and top it all with maple syrup, butter, fresh fruit, or a shower of confectioners’ sugar. There’s no wrong way to eat this unbelievable goodness! Just as long as you go back for seconds.
Unbelievable Blueberry French Toast Casserole
- 1 (12-14 ounce) loaf french bread, sourdough bread, or challah1
- 1 cup (180g) fresh or frozen blueberries2
- 8 large eggs
- 2 and 1/4 cups (540ml) whole milk
- 1/2 teaspoon ground cinnamon
- 3/4 cup (150g) packed light brown sugar
- 1 Tablespoon (15ml) vanilla extract
- 1/3 cup (69g) packed light brown sugar
- 1/3 cup (42g) all-purpose flour (spoon & leveled)
- 1/2 teaspoon ground cinnamon
- 6 Tablespoons (86g) unsalted butter, cold and cubed
- Optional: extra blueberries, fresh fruit, maple syrup, and/or confectioners' sugar for topping
- Grease a 9x13 inch pan with butter or spray with nonstick spray. Slice then cut the bread into cubes, about 1 inch in size. Spread cubes into the prepared baking pan and top evenly with blueberries. Set aside.
- Whisk the eggs, milk, cinnamon, brown sugar, and vanilla together until no brown sugar lumps remain. Pour over the bread. Cover the pan tightly with plastic wrap and stick in the refrigerator for 3 hours - overnight. Overnight is best.
- Preheat oven to 350°F (177°C). Remove pan from the refrigerator.
- Prepare the topping: Whisk the brown sugar, flour, and cinnamon together in a medium bowl. Cut in the cubed butter with a pastry blender or two forks. Sprinkle the topping over the soaked bread.
- Bake for 45-55 minutes or until golden brown on top. I usually bake it for 45 minutes because I like it softer. Serve immediately. Cover leftovers tightly and store in the refrigerator for 2-3 days.
Make ahead tip: Prepare the topping in advance, cover tightly, and store in the refrigerator. Sprinkle over the soaked bread before baking. For freezing, prepare the recipe through step 4 (without preheating the oven) and freeze for up to 2 months. Thaw overnight in the refrigerator then bake as directed. Baked casserole can be frozen up to 3 months. Thaw overnight in the refrigerator and warm up in a 350°F (177°C) for 35 minutes or until warm in the center.
This recipe can easily be halved in an 8 or 9-inch baking pan. The bake time will be slightly less, around 30-35 minutes.
- Day-old, crusty bread is perfect for french toast casseroles. I typically use a loaf of challah bread that I slice and let sit out overnight. You'll wind up with about 12 cups of cubed bread. A little more or less is OK.
- Instead of blueberries, try strawberries, raspberries, or blackberries. In the fall, try cranberries or thinly sliced apples or pears. So many options!
Did you make a recipe?
Tag @sallysbakeblog on Instagram and hashtag it #sallysbakingaddiction.
With kitchen-tested quality recipes and step-by-step tutorials, my goal is to give you the confidence to bake and cook from scratch.