Packed with peanut butter, chewy oats, and oodles of chocolate chips and M&M’s, these flourless monster cookies are simply unbelievable. I tried and tested this recipe multiple times over the past year, with various groups of taste testers, and, trulyโno one believed there isn’t any flour.
No flour means more peanut butter flavor. Let’s do this!
Have you ever made big giant monster cookies, soft and thick monster cookies, or these big fat peanut butter oatmeal chocolate chip cookies before? They’re two reader (and personal!) favorites. Today’s cookies are a lot like those… but with less sugar, less butter, andโdid I mention this?โno flour. Yet, magically, they’re somehow just as delicious.
Not one of the many very satisfied taste testers (including an entire tee-ball team!) missed the flour at all in these cookies!
What Are Monster Cookies?
The label soft and thick monster cookies refers to an all-in-one combination of several different types of cookies: a monster mash-up of peanut butter cookies, oatmeal chocolate chip cookies, and M&M cookies! Like Frankenstein’s monster, if Dr. Frankenstein were a baker. (And that would have been a very different story.) My recipe today is for flourless monster cookies.
Here’s What You’ll Love About These Flourless Monster Cookies
- Naturally gluten free, if using certified GF oats
- Chewy, peanut buttery, and loaded with chocolate chips and M&M’s
- Easy dessert recipe that doesn’t require a mixer
- Only 30 minutes of dough chilling time, so they can be ready in an hour!
Grab These Ingredients
- Oats: Old-fashioned whole rolled oats are the base for these chewy cookies. If needed, use certified GF oats to ensure the cookies are gluten free.
- Baking Soda: For a little lift, to counteract the weight of the peanut butter.
- Salt: Flavor enhancer/sweetness balancer.
- Butter: Just a little bit of melted butter goes a long way in adding delicious flavor and even more chewiness, just like in chewy chocolate chip cookies.
- Brown Sugar: Light brown sugar sweetens, and keeps the cookies moist.
- Eggs: These provide structure and richness, while binding all the ingredients together.
- Vanilla Extract: Another key flavor enhancer in most cookie recipes. You can use homemade vanilla extract or store-bought, either works!
- Peanut Butter: I recommend using creamy processed peanut butter for this recipe, like Jif or Skippy. Whether you’re making these cookies, peanut butter blossoms, peanut butter fudge puddles, or really any peanut butter-based cookies, processed creamy peanut butter will give you the best taste and soft-baked texture.
- M&M’s: You can use either mini or regular-size M&M’s in these cookies. I like to use the color-themed holiday edition M&M’s if I’m making these for a holiday or party.
- Chocolate Chips: Because, obviously.
Expect a Gooey, Sticky Cookie Dough
The cookie dough comes together in 2 bowlsโone for the wet ingredients, and one for the dry ingredients. Then stir everything together with a silicone spatula. It may take a bit of arm muscle, but it will come together. Finally, add the chocolate chips and M&M’s, folding them in with the spatula.
This is a gooey, sticky cookie dough. And, like many other cookie recipes I publish, refrigerating the dough before baking it helps ensure the cookies hold their shape. 30 minutes is plenty, which gives you just enough time to line your baking sheets, grab your cookie scoop, and preheat the oven. (Or, if you’re feeling ambitious, you can use the time to prepare and bake a no-chill recipe like shortbread cookies or coconut macaroons!)
**Chilling is one of my top tips for how to prevent cookies from overspreading.**
When you’re ready to bake, scoop mounds of cookie dough (a heaping 2 Tablespoons in size, about 45g each). A medium cookie scoop is helpful with the sticky dough, but make sure it is a heaping scoop to yield the proper amount of cookie dough. Then bake on a lined baking sheet until the edges are set. The centers will still look a bit soft, and that’s ok. Mine take about 14 minutes in the oven.
FAQ: Can I Make These Nut-Free?
Yes. The team & I tested these flourless monster cookies with sunflower seed butter in place of the peanut butter, and the recipe works. However, keep in mind that when sunflower seed butter and baking soda combine, there’s a natural reaction that causes the inside of the cookies to turn green! It’s harmless and doesn’t change the taste or texture. The kids loved it. ๐ (Now they’re really Dr. Frankenstein’s monster cookies!)
This recipe is part of my annual cookie countdown called Sally’s Cookie Palooza. It’s the biggest, most delicious event of the year! Browse dozens of cookie recipes over on the Sally’s Cookie Palooza page.
Flourless Monster Cookies
- Prep Time: 40 minutes
- Cook Time: 14 minutes
- Total Time: 1 hour
- Yield: 18โ20 cookies
- Category: Cookies
- Method: Baking
- Cuisine: American
Description
Packed with peanut butter, chewy oats, and oodles of chocolate chips and M&M’s, these flourless monster cookies are a monster mash-up of favorite cookie types. I promise you won’t miss the flour at all! Be sure to refrigerate the sticky cookie dough for at least 30 minutes before shaping and baking.
Ingredients
- 1 and 1/2 cups (128g) old-fashioned whole rolled oats
- 1 teaspoon baking soda
- 1/8 teaspoon salt
- 3 Tablespoons (43g) unsalted butter, melted
- 2/3 cup (133g) packed light or dark brown sugar
- 2 large eggs, at room temperature
- 1 teaspoon pure vanilla extract
- 1 cup (250g) creamy peanut butter (see note)
- 1/2 cup (105g) regular-size M&M’s, or 1/3 cup (77g) mini M&M’s
- 1/3 cup (60g) semi-sweet chocolate chips
Instructions
- In a medium bowl, whisk the oats, baking soda, and salt together until combined. Set aside.
- In a large bowl, whisk the melted butter, brown sugar, eggs, and vanilla together until combined. Whisk in the peanut butter.
- Pour the dry ingredients into the bowl with the wet ingredients and mix with a silicone spatula until combined. (Takes some arm muscle!) Fold in the M&Ms and chocolate chips. The dough will be sticky and gooey.
- Cover the cookie dough tightly and chill in the refrigerator for at least 30 minutes and up to 3 days.ย
- Preheat oven to 350ยฐF (177ยฐC). Line large baking sheets with parchment paper or silicone baking mats.
- Scoop the dough, a heaping 2 Tablespoons (45g) each, and place the mounds of cookie dough about 3 inches apart on the prepared baking sheets. (A medium cookie scoop helps with the sticky dough, but make sure it is a heaping scoop to get you 2 Tablespoons (45g) of dough.)
- Bake until the edges are set and golden brown, about 12โ15 minutes. The cookies will still look soft in the centers.
- Cool cookies for 10 minutes on the baking sheet. During this time, I like to press a few more chocolate chips or M&M’s into the tops of the warm cookies. (This is optional and only for looks.) Transfer to wire rack to cool completely.
- Cover leftover cookies tightly and store at room temperature for up to 1 week.
Notes
- Make Ahead & Freezing Instructions: You can make this dough ahead of time and keep it in the refrigerator for up to 3 days. Baked cookies freeze well for up to 3 months. Unbaked cookie dough balls freeze well for up to 3 months. Bake frozen cookie dough balls for an extra minute, no need to thaw. Read my tips and tricks on how to freeze cookie dough.
- Special Tools (affiliate links): Glass Mixing Bowls | Whisk | Silicone Spatula | Cookie Scoop | Baking Sheets | Silicone Baking Mat or Parchment Paper Sheetsย | Cooling Rack
- Oats: Oats are naturally gluten free, but if you have dietary restrictions, be sure they are labeled “certified gluten free” because oats can be packaged in a facility with gluten.
- Can I Use Quick Oats? You can certainly try it. The cookies will not spread as much, and you’ll lose some of the chewy texture.
- Peanut Butter: I strongly recommend using processed creamy peanut butter for these cookies, such as Jif or Skippy. Using natural peanut butter will make for a drier, more crumbly cookie.
- Nut-Free: We tested these cookies with sunflower seed butter in place of the peanut butter, and the recipe works; but keep in mind that when sunflower seed butter and baking soda combine, there’s a natural reaction that causes the inside of the cookies to turn green! It’s harmless and doesn’t change the taste or texture.
- Be sure to check out my top 5 cookie baking tips AND these are my 10 must-have cookie baking tools.
Reader Comments and Reviews
Not our favorite, it seems like maybe something is missing…more sugar?
This is a terrible recipe. Cookies are flat, baked terribly and the texture is off. Avoid this one.
Hi Pat, Iโm so sorry these didnโt turn out for you. Thatโs never the experience I want anyone to have. These cookies are naturally on the chewy side, but they shouldnโt bake up flat or uneven. It sounds like something may have been off with the peanut butter consistency or baking time (a thinner or warm peanut butter can cause spreading). Which brand of peanut butter did you use? Iโd be happy to help troubleshoot more. Thank you for giving the recipe a try and for sharing your honest feedback.
Can I grind the oats into a flour like consistency? Do you know what I could expect from the finished product?
Hi Jeannette, we haven’t tested it, but we fear the cookies would be much too dry, won’t spread as much, and will lose their chewy texture.
I love how customizable these monster cookies are. I added pretzel bits and it was a game-changer! Great post.
I normally love all the recipes I make from this site but this one was definitely a flop, the cookies were bland and a strange consistency, chewy but unsatisfying. It felt like I could pull the cookie in half by pulling on both ends, like it wasn’t very solid. Maybe if you like very chewy cookies you would like this but to me the texture made them taste stale. I tried baking some one of the batches extra long to crisp up the outside and sprinkling salt on it, which helped a little.
I have loved every recipe Iโve made from this site. This is the first time it did not work. Iโve made monster copies many times, but thought Iโd try this recipe since I love Sallyโs recipes. The dough seemed off from the start-it was very soft, almost runny. I did a test bake and these cookies are very airy, not chewy at all and not quite sweet enough, in my opinion. The only โmodificationโ I made was to double the recipe, unfortunately.
Wonderful recipe! Definitely a keeper!
These are so good!!! Sweet but not too sweet and they have such a good chewy texture. Thanks for the recipe!
Have you ever mixed in some crushed GF pretzels? Would that throw off the balance of ingredients? First time baking Xmas cookies for my celiac kiddo!
Sally is the BEST but these weren’t too tasty. Tasted pretty bland. I’m gluten free – I eat Mel’s gluten free cookies and THOSE are amazing
Can I substitute honey for molasses?
Hi Daria, there is no molasses in this recipe. But in our other oatmeal cookie recipes, you can just leave the molasses out if you don’t have any.
These look fantastic. Can these be made as a cookie bar? If so, pan size, temp and time suggestions. Thanks!
Hi Doreen, I’m sure they could but I haven’t tried it. I would use a 9-inch square pan.
More of a granola bar recipe
This was one of the best recipes!!! Question: my family ate a lot of this rare, could I leave the eggs out and make it like an energy ball?
Hi Victoria, we fear the dough will not hold together without the eggs. It would be best to find an energy ball recipe instead. We’re glad these were a hit!
I was doubtful the recipe was using enough rolled oats, but after a night in the fridge, these little yummies baked beautifully! I reduced the brown sugar to 1/2 c (they are still plenty sweet for my taste buds) and the butter to 2 T, and found that these healthier monster cookies are long on flavor and texture. YUM! Easy to make, easy to bake.
Is there a variation available using stevia instead of brown sugar, and raisins & walnuts instead of candy?
Hi Fran, you can swap the candies with the same total amount of raisins and walnuts. We’d love to help but we are not trained in baking with sugar substitutes. For best taste and texture (and so you don’t waste your time trying to adapt this recipe since it may not work properly), it may be more useful to find a recipe that is specifically formulated for sugar substitutes like Stevia. Thank you!
I make these every week – they are WONDERFUL and are my breakfast cookie ๐ I use a little Stevia and had no issues – I do add a few more oats, raisins and whatever nuts I feel like.
Absolutely yummy! Could not tell it was gluten free. Peanut butter taste was not over powering like I thought it was be. Just a nice, moist, chewy cookie.
This was recipe was a hit! And you are right, it’s almost unbelievable there isn’t flour in them; you can’t tell! It’s a great gluten free recipe that isn’t obviously gluten free in flavor ๐
I bought crunchy peanut butter on accident, but it worked great!
Hi there! I made the recipe but found it a tad too sweet, do you think I could omit the sugar totally in this recipe? Or at least halve it? I’m not sure if the texture would change much.
Also, my cookies didn’t really spread! Should I try baking it without pre-chilling? Thanks so much in advance ๐
Hi Marianne, we donโt recommend it โ sugar provides necessary taste, texture, and structure. You can try reducing it slightly, but expect a different cookie depending on how much you reduce. If you happened to have used quick oats, the cookies may not have spread as much. You could try skipping the chilling!
I was so excited about this recipe! My cookies turned out very cakey. Is that the way the are supposed to be? Love your recipes!!
Hi Suji, these should be quite chewy, not cakey. Perhaps the oats were over-measured – make sure to spoon and level when measuring oats (or use a kitchen scale for most accurate results!).
I absolutely love these cookies! Thank you:)
Have you figured the nutritional value for these per cookie?
Hi Emily, so glad these were a hit! We donโt usually include nutrition information as it can vary between different brands of the same ingredients. Plus, many recipes have ingredient substitutions or optional ingredients listed. However, there are many handy online calculators where you can plug in and customize your exact ingredients/brands. If you’d like to calculate it, readers have found this one especially helpful: https://www.verywellfit.com/recipe-nutrition-analyzer-4157076
Thank you! ๐
I love these cookies. But I have a question. I have a relative that is allergic to dairy. Can you substitute crisco for the butter in these cookies
Hi Patty! Crisco isn’t a 1:1 swap. We would search for a dairy-free monster cookie recipe instead, like this recipe from Cookie & Kate: https://cookieandkate.com/monster-cookies-recipe/
These are excellent! I was a little dubious because the dough was so sticky, even after being in the fridge for a half hour, but they baked up beautifully in 12 minutes and look just like the photos!
So delicious! I did end up using gf quick oats, but everything else was the same. 14 minutes on 350…. Perfect!