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This simple and customizable recipe for gluten free monster cookies is packed with peanut butter, oats, and chocolate. Plus, they're made without any rice flour or flour blend at all.
Why you'll love these monster cookies
The hearty, chewy texture, derived from the clever use of old-fashioned rolled oats and oat flour, creates a satisfying and filling cookie. Their versatility allows you to adapt the recipe to suit your preferences or cater to other dietary restrictions easily.
The simple preparation method minimizes cleanup and makes the baking them really easy. The base is very similar to a classic gf oatmeal cookie, but since there's no all purpose flour at all and only whole grains, it's heartier and has more of the nutty, chewy flavor of oats.
The cookie is bound together with an egg, an egg yolk, and peanut butter. Along with oat flour and gluten free quick oats, the combination creates a chewy cookie that's really stable (great for shipping in a care package!) and crispy on the outside.
The candy shell on the miniature chocolate M&Ms candies in these peanut butter oatmeal M&M cookies adds even more texture to these sweet chocolate chip cookies.
Key ingredients
- Gluten free quick oats – Since these are gluten free monster cookies, be sure to use gluten free oats. You can begin with rolled certified gluten free oats and process them briefly in a blender or food processor, or buy gluten free quick oats, which are already more processed.
- Oat flour – Since this recipe also has quick oats which have texture, we don't need a very smooth, sifted oat flour. Rather than buying oat flour like I do for my oat flour brownies, I just grind some of my old fashioned or gluten free quick oats into oat flour in a blender or food processor.
- Butter – Your butter should be at “room temperature,” which means that you can leave a fingerprint in it, but your finger doesn't come away greasy
- Gluten free peanut butter – I love baking with no-stir smooth peanut butter, since it combines so well with other ingredients, much like room temperature butter does. I usually buy Skippy brand.
- Eggs – We use 1 whole egg for lift and as a binder, and 1 egg yolk, which helps soften the cookies' texture (peanut butter tends to make baked goods crunchy)
- Light brown sugar – Light brown sugar has more moisture from the added molasses than granulated sugar; it tenderizes cookies and adds depth of flavor
- Chocolate chips and mini M&Ms – Some people make monster cookies with regular size M&Ms, but I really prefer semi-sweet chocolate chips, and miniature M&Ms for added texture and flavor.
How to make gluten free monster cookies
Mix dry ingredients, then wet
- First, mix the dry ingredients (oat flour, quick gluten free oats, baking soda and salt) in a separate bowl.
- Mix the butter, gluten free peanut butter, egg and egg yolk, vanilla and brown sugar separately. This makes it easier to get the lumps out of the brown sugar.
- Add the oat and oat flour mixture to the wet ingredients.
Combine wet and dry ingredients, and portion the cookie dough
- Mix the dry ingredients into the wet until just combined.
- Add the chips and candies, and mix again gently to combine.
- Scoop the dough into mounds with a medium ice cream scoop placed about 2 inches apart from one another. Aim to make the pieces of dough about 2 1/2 tablespoons each.
Press into disks and bake at 350°F
- With wet fingers, press the cookie dough into disks about 1/2-inch thick
- Bake at 350°F/177°C for about 14 minutes or until the cookies are lightly brown on the edges and the cookies look crackled on top.
- Allow the cookies to set on the baking sheet for a few minutes before moving them, or they'll fall apart. After cooling, the cookies are very stable.
Recipe tips & tricks
This recipe is so easy, it's difficult to get wrong. But, there are a few quick tips that ensure your gluten free monster cookies are the best they can be.
Use a combination of oats and oat flour
Baking with oats (which substitute for oats, if you're unable or unwilling to eat them!) can be tricky. Old fashioned rolled oats, which are one of the least processed forms of oats, are relatively thick.
One way to make a stable cookie that holds together is to add a rice flour blend to it. But like in our oatmeal breakfast cookies, here I simply ground some old fashioned rolled oats into a flour in a food processor and added that to the recipe.
The rest of the oats in this recipe are quick-cooking oats. Rather than buying gluten free quick oats, I usually just pulse old-fashioned oats a few times very quickly in a food processor.
Use an ice cream scoop for easy portioning
Right after the dough is assembled, scoop large rounded balls of dough using a spring-loaded ice cream scoop that's packed tight to help create a round shape. If you have trouble getting the cookie dough out of the scooper, rinse it with warm water in between scoops.
Use no-stir peanut butter for better results
Truly all natural peanut butter that requires stirring is usually too oily for baking, and tends to separate in the cookie dough. No-stir peanut butter has emulsifiers that keep the oil mixed in to the nut butter.
Use parchment paper for quick cleanup
Line your baking sheets and pans with parchment paper to ensure even baking, and to make cleanup a breeze. I keep and reuse sheets of parchment multiple times, to avoid so much waste.
Don't mix too much
When baking with oat flour especially, the baked goods can become tough if you work the batter or dough too hard. This way, the oats can be handled much less when everything is combined.
Making gluten free monster cookie dough in advance
You can make this gluten free monster cookie dough ahead of time, as long as you shape the balls of cookie dough right after you make the mixture. As the cookie dough sits, the oils get more fully absorbed into the flours, and the dough may not hold together as well. Just shape the cookie dough balls, then cover the portions and you can bake it hours later.
Refrigerating gluten free monster cookies dough
If you'd like to make the monster cookie dough farther in advance, you can refrigerate the shaped portions for 2 to 3 days. Be sure to cover them first so they don't dry out, and allow the cookie dough to come to room temperature before baking.
Freezing gluten free monster cookies dough
For longer storage, try flash freezing the dough balls on a baking sheet in a single layer. Transfer them to a zip-top bag for longer storage. To ensure that the cookies spread properly, let them come to room temperature before baking.
How to store monster cookies
Monster cookies are really stable and stay fresh for days in a sealed glass container at room temperature. Don't store them in a plastic container at room temperature, or they'll lose their crisp exterior and become more fragile.
Freezing baked monster cookies
You can freeze these baked monster cookies in a freezer safe zip-top bag and enjoy them right from the freezer, or warmed up a bit in the microwave or on the counter. Squeeze as much air as possible out of the bag to avoid freezer burn.
Popular ingredient substitutions
These crisp-outside, chewy inside cookies have a fair number of additional allergens in them. Here are my best guesses for how to avoid them.
Please keep in mind that this recipe was formulated to work precisely as written. The more substitutions you make, the more you are veering toward a separate recipe entirely.
Dairy-free
The only dairy in these cookies is from the unsalted butter and the M&Ms chocolate candies. The M&Ms can easily be replaced with more chocolate chips, and you can of course use dairy free chocolate chips.
I haven't tried replacing the butter, but you should be able to use Melt or Miyoko's Kitchen brand vegan butter. I don't generally like Earth Balance buttery sticks because they have so much moisture which will likely cause the cookies to spread too much during baking.
You can also try replacing the butter with virgin coconut oil. It's the type that's solid at cool room temperature.
Egg-free
The single whole egg in this recipe should be able to be replaced with 1 “chia egg” (1 tablespoon ground white chia seeds + 1 tablespoon lukewarm water, mixed and allowed to gel).
The egg yolk is in the recipe for moisture, so you can try replacing it with about a tablespoon or so of smooth applesauce. I'm afraid you'll just have to experiment!
Peanut butter-free
If you need to make this recipe without gluten free peanut butter, I'm sure a similar style of almond butter (like Barney Butter) would work great. I also have a recipe for Nutella monster cookies that is peanut-free.
If you need the recipe to be nut-free, you can try replacing the nut butter with Wowbutter, made with toasted soy nuts, which seems nice and creamy. You could also try sunflower seed butter, but your cookies may spread more, and they may even turn a harmless green color when mixed with baking soda.
Oat-free
In baking, oat flour can often be replaced with quinoa flakes, and old-fashioned oats can be replaced with beaten rice or sometimes coconut flakes/chips. For more information, see our post on how to substitute for oats.
More delicious mix-ins for gf monster cookies
- For even more peanut flavor, try replacing some of the mix-ins with chopped roasted peanuts or other chopped nuts.
- Swap in white chocolate chips instead of some or all of the semi-sweet chocolate chips.
- Add crushed mini gluten free pretzel twists or sticks instead of some of the chocolate chips or mini M&Ms
FAQs
Monster cookies are basically just peanut butter cookies or oatmeal cookies with M&M chocolate candies and chocolate chips mixed in. They're called “monster cookies” since they're like the Frankenstein's monster of cookies.
I specify “no-stir”, regular creamy peanut butter in this recipe, as I do in most recipes that I write that contain peanut butter as an ingredient. All “no-stir” means is that the oil in the jar of peanut butter doesn’t separate significantly from the rest of the nut butter in the jar.
Most commercially prepared peanut butter is no-stir. My favorite brand is Skippy, since it's great-tasting, always smooth, and all varieties of Skippy are gluten free. but I also sometimes use Barney Butter—although it tends to be quite expensive. Even Skippy “Natural” peanut butter says on the outside that there's “no need to stir.”
Chunky peanut butter doesn't mix in quite as well as smooth peanut butter in this recipe, so I'd avoid using it in this recipe. Stick with the creamy smooth peanut butter, and replace some of the chips or mini M&Ms with some chopped peanuts for a nutty crunch if you'd like that.
If your butter was melted or oily because it was too warm, your cookies may spread too much and come out flat.
If you live in the U.S., most plain varieties of M&Ms chocolate candies are gluten free. I do understand that if you're in Australia, M&Ms aren't gluten free. Just use miniature chocolate chips or even raisins.
No, these cookies can't be made with almond flour, since it has very different qualities from oats. Sometimes, it works to replace oat flour with blanched almond flour, but I haven't tried that. And, of course, you'll still need rolled oats or a substitute for oats.
Gluten-Free Monster Cookies Recipe
Ingredients
- 1 cup (120 g) oat flour, (certified gluten free if necessary) (See Recipe Notes)
- 1 ½ cups (150 g) quick cooking oats, or rolled oats, processed slightly in a food processor or blender (certified gluten free if necessary) (See Recipe Notes)
- ¾ teaspoon baking soda
- ¼ teaspoon kosher salt
- 4 tablespoons (56 g) unsalted butter, at room temperature
- ½ cup (128 g) smooth, no-stir peanut butter, the kind that doesn't separate in the jar
- 1 (50 g (weighed out of shell)) egg, beaten, at room temperature
- 1 (25 g) egg yolk, at room temperature
- 1 teaspoon pure vanilla extract
- 1 cup (218 g) packed light brown sugar
- 5 ounces semi-sweet chocolate chips
- 5 ounces miniature M&Ms chocolate candies, (gluten free in the U.S.)
Instructions
- Preheat your oven to 350°F. Line a rimmed baking sheet with unbleached parchment paper and set it aside.
- In a medium-size bowl, place the oat flour, oats, baking soda, and salt, and whisk to combine. Set the bowl aside.
- In a large bowl, place the butter, peanut butter, egg and egg yolk, vanilla, and brown sugar, and mix well. Add the oat flour mixture to the large bowl, and mix until just combined.
- Add the chocolate chips and M&Ms candies and mix until the pieces are evenly distributed throughout the dough. The dough will be thick but should not be stiff.
- Using a spring-loaded ice cream scoop or two spoons and scoop the dough into mounds about 2 1/2 tablespoons each onto the prepared baking sheet, about 2 inches apart from one another.
- Using wet fingers, press each mound down into a disk about 1/2-inch thick.
- Place the baking sheet in the preheated oven and bake for 12 to 14 minutes, or until the cookies are lightly brown around the edges, set in the center and the top of each cookie has taken on a crackled appearance.
- Allow the cookies to sit on the baking sheet for 10 minutes or until set. Serve slightly warm or at room temperature.
- These cookies also freeze amazingly well in a sealed freezer-safe container.
Video
Notes
I don't often buy oat flour or even quick-cooking oats. For gluten free quick oats, I just process old-fashioned rolled oats in a food processor or blender for a few pulses. You can make oat flour by grinding rolled oats quite a bit more, and that's perfect for a recipe like this. I do buy oat flour when I need a very finely ground, sifted product. Nutrition information. Nutrition information is an estimate, per cookie, based on information from an online calculator. It is provided as a courtesy and should not be relied upon.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
These look so good but I need sugar free and gluten free. Do you have any recipes like this?
Thank you,
Betty
You can try using your favorite alternative sugar replacements, Betty, but I’m afraid I don’t have recipes that are specifically sugar-free. Sorry!
M&M’s in Canada other than pretzel ones are gf. They do recommend always checking the label of course. Great recipe!
Great to know, Jeanette! Thanks for sharing that info.
Most oatmeal including the namebrand is not gluten free so the company told me so make sure
it’s gluten free if you are going for gluten free. I’m wondering about subbing almond flour??
Yes, Karen, if you are gluten free, your oats should be certified gluten free. Please see a full discussion here. You cannot use almond flour in place of oats. Please see the “ingredients and substitutions” section of the post for information on substitutions.
I read the title of your cookie Nicole, as it specifically says Gluten Free. I have Celiacs and am weary of any recipe that includes Oats. But after reading your comments, suggestions and recipe I am doubtful and too afraid that this recipe would make me ill and send me to the hospital. Too often the words Gluten Free are casually used in a title and then after further reading, I discover the gluten-free terminology isn’t taken seriously. True gluten free does not include Oats. For those without Gluten issues, your recipe sounds like a good chewy & tasty cookie. Best wishes to you and your future recipes.
Rosalind, if this recipe isn’t for you, then, of course, feel free to pass it on by. You are ultimately responsible for your own health. But I’ve never used the term “gluten free” casually or lightly, having a celiac son and writing a gluten free blog since 2009. I find your statements about oats to be overbroad and inaccurate.
I made a double batch today, no M&Ms, doubled the chocolate chips. They are outstanding! Thanks for the great recipe!
Awesome, Gayle! I love that you went all in with the double batch right away. ?
Thank you so much for the recipe. I have never made Monster cookies, these were quick and easy! I did have to make 1 substitution because I am not sure Mini M&Ms are GF in Canada. I used Mini Reeses pieces and loved them in there. I am not claiming any improvements, just thought other Canadians would be interested too.
That’s definitely useful information, Leann! And it sounds like a great combo. Thanks for the report!
Thank you for making a cookie recipe that is rice flour free!
You’re welcome, Ireann! If you can’t have rice flour, definitely check out two categories here on the blog: Paleo recipes, and flourless baking.
I have celiac disease. Always looking for recipes.
I appreciate you sharing this recipe and alterations.
My daughter did the gluten-free test with me. So, now I’m looking for recipes I can make and afford.
Your time and understanding spirit are appreciated.
My pleasure, Carol. Welcome!
Will this recipe work with gluten-free baking flour instead of the oat flour?
I haven’t tried that, Valerie, but I’m afraid I really don’t recommend it. It sounds like you’re looking for something more like my recipe for thick and chewy gluten free oatmeal cookies.