Tessa’s Recipe Rundown
TASTE: Loads of peanut butter, oats, chocolate chips, and M&Ms make these cookies so much FUN!
TEXTURE: Delightfully chewy thanks to the oats and peanut butter, with a subtle crunch from the chocolate chips and M&Ms throughout.
EASE: So easy! These cookies are ready to enjoy in just 33 minutes.
PROS: Quick and easy cookies.
CONS: None.
WOULD I MAKE THIS AGAIN? I’ve made these cookies countless times!
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Monster Cookies are about to be the most fun oatmeal cookies you’ve ever tasted!
I love oatmeal cookies. There’s something so special about the chewy texture and the delightful, almost nutty flavor that oats bring to baked goods. That’s why I’ve created so many fantastic oatmeal cookie recipes, like my classic Oatmeal Chocolate Chip Cookies, craveworthy Peanut Butter Oatmeal Chocolate Chip Cookies, and my copycat Homemade Oatmeal Cream Pies.
These Monster Cookies are one of my favorite treats, whether it’s Halloween, Christmas, or just any time I’m craving peanut butter and chocolate…which is basically every day, ha!
They’re also the perfect quick and easy snack to make with kids. They’ll love adding extra M&Ms to the tops of each cookie!
Naturally gluten-free (when you buy certified gluten-free ingredients), these cookies are the perfect crowd-pleaser for Halloween parties, Christmas cookie platters, or simply as a fun weekend treat.
Sprinkle of Science
How to Make Monster Cookies
No Flour in This Monster Cookies Recipe?
Yes, these Monster Cookies are flourless cookies. The peanut butter, oats, and egg + egg yolk provide enough structure to hold everything together and bake into a chewy delight.
The lack of flour does change the texture of the dough. It will feel a bit loose and won’t hold together like a traditional cookie dough. This means that a few of the M&Ms and chocolate chips may fall out as you portion out the dough. That’s okay – simply add them back on top of each cookie dough ball!
What Type of Peanut Butter for Monster Cookies?
I recommend using natural peanut butter that’s been very well stirred (to avoid any oily pockets or dry bits). My favorite is Kirkland Organic (high quality and a great price at Costco!). Natural peanut butter will yield a much bolder peanut butter flavor in these Monster Cookies. If you don’t have any, conventional peanut butter (Skippy / Jif) works well too.
What Type of Oats for Monster Cookies?
Use old-fashioned rolled oats for Monster Cookies. Don’t use quick oats, which can make the cookies mushier and less chewy. Be sure to measure correctly, as accidental over-measuring can cause dry, hard, crumbly cookies. Learn more about how to measure ingredients correctly here.
Do I Have to Use Dark Brown Sugar?
I recommend using dark brown sugar for its added flavor and moisture to achieve a rich and chewy cookie. You can substitute it with light brown sugar in a 1:1 ratio, but note that your cookies may turn out lighter in color and slightly less moist.
Can I Use Almond Butter Instead?
We haven’t tested that in this Monster Cookie recipe, but a straight 1:1 swap of almond butter instead of peanut butter works perfectly in my Classic Peanut Butter Cookie recipe. Let me know if you give that a try here!
What Size Are These Monster Cookies?
I use a large 3-tablespoon cookie scoop to create perfectly chewy cookies. You can use a medium 1.5-tablespoon scoop instead and reduce the bake time slightly, but keep in mind that the smaller cookies won’t be as chewy.
Can I Mix up the Mix-Ins?
Yes! Feel free to use peanut butter chips, Reese’s Pieces, or any other variety of mix-ins you like in these Monster Cookies – just keep the total weight/volume the same amount as stated in the recipe for best results.
How to Prevent M&Ms From Cracking as They Bake
- Some bakers say that mini M&Ms are less likely to crack, and others claim that freezing your M&Ms prior to baking prevents cracking. I haven’t tested either theory, so I can’t say for sure how well they work.
- Instead, if the cracking bothers you, I recommend adding the additional M&Ms to the tops of each baked cookie as soon as they come out of the oven, before they have fully set.
- Be sure to press the M&Ms into each cookie thoroughly to ensure they adhere properly.
Can I Double This Recipe? Can I Halve This Recipe?
Yes! Double all ingredients to yield approximately 34 large cookies, or halve all ingredients to yield 8-9 large cookies. No other modifications needed.
Do I Have to Chill Monster Cookie Dough?
No, you can bake these Monster Cookies right after preparing the dough – but for extra chewy, ultra-flavorful cookies with a ton of PB flavor, I recommend chilling the cookie dough for 24 to 48 hours. Avoid chilling any longer, as oats tend to zap moisture and these cookies will dry out. Learn more about how to chill cookie dough here.
How to Store Monster Cookies?
Monster Cookies can be stored in an airtight container at room temperature for up to 3 days. Store with a tortilla to keep the cookies softer for longer.
Can You Freeze Monster Cookies?
- Yes, Monster Cookies freeze well!
- I recommend chilling the portioned balls of cookie dough for 24-48 hours before freezing to achieve the best chewy, flavorful cookies.
- After the chill period, place cookie dough balls in a single layer on a parchment-lined rimmed baking sheet and place in the freezer until solid, then remove the cookie dough balls to a labeled and dated airtight container.
- When you’re ready to bake the cookies, bake directly from the freezer by reducing the oven temperature to 325°F and adding a minute or two to the bake time.
- Alternatively, thaw the cookie dough balls in the refrigerator overnight before baking as directed below.
- Learn more about How to Freeze Cookie Dough (& Bake From Frozen) here.
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Monster Cookies
Ingredients
- 4 tablespoons (57 grams) unsalted butter, at cool room temperature
- 3/4 cup (203 grams) natural peanut butter, very well stirred*
- 1/2 cup (100 grams) granulated sugar
- 1/2 cup (100 grams) lightly packed dark brown sugar**
- 1 large egg plus 1 egg yolk, at cool room temperature
- 1½ teaspoons vanilla extract
- 2 cups (198 grams) old-fashioned rolled oats
- 1 teaspoon baking soda
- 1/4 teaspoon salt
- 1/2 cup (85 grams) semisweet chocolate chips, plus extras to top cookies, optional
- 1 cup (200 grams) M&M candies, plus extras to top cookies, optional
- Flaky sea salt, for topping, optional
Instructions
- Preheat the oven to 350°F. Line baking sheets with parchment paper.
- In the bowl of an electric mixer, beat the butter, peanut butter, granulated sugar, and brown sugar on medium-high speed until smooth and creamy, 2 to 3 minutes. Scrape down the bottom and sides of the bowl. Beat in the egg, egg yolk, and vanilla. Add the oats, baking soda, and salt, mixing on low speed until combined. Fold in the chocolate chips and M&Ms with a rubber spatula.
- Using a large spring-loaded scoop, measure out 3 tablespoon-sized balls of dough. Press the dough firmly into the scoop before placing it onto prepared baking sheets, spacing at least 2 inches apart. Dough will be loose. Dot the tops of cookies with a few M&Ms and/or chocolate chips before baking for picture-perfect cookies.
- If time permits: wrap the cookie dough balls very well in plastic wrap and allow to “marinate” in the fridge for 24-48 hours to enhance flavor and texture.
- Bake for about 13 minutes, or until the edges are slightly browned. Remove from oven and sprinkle flaky sea salt on top of the cookies, if desired. Cool for 5 minutes before removing to wire racks. For best texture and to allow the peanut butter flavor to fully develop, let cookies cool completely before serving.
- Cookies can be stored in an airtight container at room temperature for up to 3 days.
Recipe Notes
Photos by Joanie Simon.
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Peanut butter, oats, M&M’s. It all worked.
Good balance with all the ingredients.
Very easy to make.
These cookies were a real crowd pleaser. I took them to a meeting with my ladies group at church. Everyone was so suprised that they were gluton free and some asked if I would share the recipe. I have a friend with Siliac disease and I’m never able to share goodies with her so she is going to love these. A very easy recipe to make and I love you don’t have to chill the dough overnight if you don’t have time. I did however chill it for about an hour and it made the dough easier to scoop.
Sweet Kudosfor this amazing recipe… Linda
So glad you and your church group enjoyed these cookies, Linda! 🙂
Unsurprisingly these cookies knocked it out of the park! I’ve yet to make a recipe from Tessa that is a dud.
Some helpful tips for this one:
I used natural PB but it was ‘no-stir’ not the kind with oil settled on top.
Trust the dough process. It will seem a bit dry/crumbly but that’s ok!
Don’t over load the add ins; the dough can only support the amount of add ins listed in the recipe.
Since the dough is crumbly sometimes my dough balls spread unevenly in the oven. This was easily fixed by nudging them back into a circle when they were fresh out of the oven.
Great tips, Meghan! So glad you enjoyed these cookies 🙂
Everyone loved them! They have a great chew! They are easy to make! Peanut butter is the best!
I loved these! Super quick to make with lots of flavor and incredible texture. This is a nostalgic cookie for me, and I’ll definitely be making them again.
Super easy and a yummy cookie, just not my fav type of cookie recipe.
Thank you for this yummy recipe! My daughter is asking for this but wants it to have a chocolate base for our Halloween party!
Would I just add cocoa ? If so how much? Thanks so much again!
Hi Ashley! So glad to hear that you enjoyed these cookies! Unfortunately, simply adding cocoa doesn’t work to make a chocolate base for a cookie. Cocoa is a very drying ingredient, and will zap the moisture from cookies, leaving you with a very dry, crumbly cookie. This recipe is even trickier, due to being a flourless cookie – so there’s no way to substitute ingredients like flour. I recommend instead experimenting with a chocolate peanut butter instead of adding cocoa (please note, we haven’t tried this, and it may not work!), or alternatively, give our delicious chocolate-based Halloween Cookies a try instead! Feel free to use Reese’s Pieces instead of the M&Ms, and sub some peanut butter chips for some of the chocolate chips, to maintain that PB and chocolate flavor. I hope that helps! Happy baking 🙂
So delicious! I had the most difficult time getting that many m&m’s and chocolate chips to stick. Yummy though!
I cant stop eating these…YUM
Good luck eating just one! These are so good and so easy to make! The best Monster Cookie recipe I have ever made.
So happy to hear how much you love them, Elizabeth!
These are easy and delicious, you won’t regret making them.
These cookies are easy and delicious, you won’t regret making them.