I'm not really sure where the name "monster cookies" originated, but based on these, I think it's because they turn you into a cookie monster. These Scary Good Monster Cookies are so delicious, you won't be able to stop eating them! No chill time is required, you can literally just plop them onto a cookie sheet and they're ready to bake! They are perfectly soft, gooey, and full of peanut butter, oats, mini M&Ms and chocolate chips! If these look tasty but you just want to eat the dough, try my Edible Monster Cookie Dough recipe!
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Monster cookies take me back to my childhood and I'm not really sure where they got lost as I transitioned into adulthood. My family used to bake them every once in a while and they were such a treat! Chocolate and peanut butter are one of my favorite flavor combinations and the oats add such a nice texture to them. I recommend using regular peanut butter over natural peanut butter in these because you don't want the oil separating from the butter in the cookies. I also like to use old fashioned oats (rolled oats) because they're bigger and give a better texture, but quick oats can be used in place of them! You can use normal sized M&Ms and chocolate chips as well, but I use mini M&Ms and semi-sweet chocolate chips because you can fit more of them into a cup (and minis are cute)!
Step by Step Instructions
STEP ONE (Picture 1 below) - Mix the dry ingredients.
In a medium bowl, stir together the flour, baking soda, baking powder, cinnamon and salt. Set them aside.
STEP TWO (Picture 2 below) - Cream the wet ingredients & stir in the dry.
In a large bowl using a hand mixer or stand mixer fitted with the paddle attachment, cream together the butter and sugars really well. Stir in the eggs, followed by the vanilla extract and peanut butter. Then, gently mix the dry ingredients into the wet ingredients just until the flour streaks are gone.
STEP THREE (Picture 3 below) - Add the good stuff.
Finally, pour the oats, mini chocolate chips and M&Ms into the dough and stir it all together. The dough doesn't need to chill, but if you want thicker cookies feel free to plop it in the refrigerator for a while.
STEP FOUR (Picture 4 below) - Scoop & bake.
I like to use a large cookie scoop for big monster cookies! Scoop the dough into balls and place them about 2 inches apart on a cookie sheet. If they lose their shape a bit after baking, give the edges a little scoot back into place with a large biscuit cutter or other round object.
Tips & Storage:
- For big & thick cookies, use a large cookie scoop instead of a small one.
- If you want the cookies to be thick but not larger, use a smaller scoop and refrigerate the dough for at least 30 minutes before baking them.
- Store monster cookies at room temperature in an airtight container with half of a piece of bread (or smaller). The cookies will absorb the moisture from the bread and stay soft longer.
- Or, store in the freezer and let the cookies thaw or microwave them prior to eating.
- You can also freeze the cookie dough balls for up to 1 month and then bake them whenever you like!
Did you try this recipe?
Tag @brokenovenbaking on Instagram and rate & comment below!
📖 Recipe
Scary Good Monster Cookies
Equipment
- Baking sheet(s)
- Mixing bowls
- Hand mixer or stand mixer with paddle recommended
- Measuring spoons
- Scale or measuring cups
- Whisk
- Spatula
- Cookie scoop
- Cooling rack
Ingredients
- ½ cup (1 stick) (113.5 g) unsalted butter room temperature
- 1 cup (200 g) light brown sugar
- ¾ cup (150 g) granulated sugar
- 2 large (2 large) eggs room temperature
- 1 tablespoon (1 tablespoon) vanilla extract
- 1 cup (253 g) creamy peanut butter
- 1 cup (125 g) all-purpose flour
- 1 teaspoon (4 g) baking soda
- ½ teaspoon (2 g) baking powder
- ½ teaspoon (1 g) cinnamon
- ¼ teaspoon (1.5 g) salt
- 1½ cups (146 g) old-fashioned oats
- 1 cup (200 g) mini M&Ms
- 1 cup (190 g) mini semi-sweet chocolate chips
Instructions
- Preheat oven to 350°F and line baking sheets with parchment paper.
- Whisk together the flour, baking soda, baking powder, cinnamon, and salt. Set aside.
- In a separate bowl, cream together the butter and sugars. Add eggs one at a time, and then the vanilla. Mix well, then add the peanut butter, and mix until fully combined. (Be sure to scrape the sides and bottom of the bowl as needed)
- Gradually add the flour mixture to the wet ingredients, mixing at low speed until the ingredients are just incorporated.
- Stir in the oats, M&Ms, and chocolate chips.
- Place dough balls on a parchment lined baking sheet, about 2 inches apart. I recommend using a large cookie scoop but a smaller one works as well!
- Bake at 350°F until the edges start to turn a light golden color (about 10-14 minutes).
- Let the cookies cool on the baking sheet for a few minutes, and then transfer to a cooling rack. Enjoy!
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Notes
More Delicious Cookie Recipes
- Honey Orange Shortbread Cut-Out Cookies (No-Chill)
- Chewy Andes Mint Chocolate Cookies
- Easy Almond Croissant Shortbread Cookies
- Soft and Easy Strawberry Sugar Cookies
- Easy Raspberry Crumble Cookies (Better than Costco)
- The Best Easy Nutella Bars
- S'mores Edible Cookie Dough Recipe
- Caramel Coconut Chocolate Chip Cookies (Levain Copycat)
Valerie Varhaug says
I made these for my cookie loving husband's birthday and I've got to say I think he fell in love with me all over again! Seriously, these cookies will put you in party mode any day. The oats, peanut butter and chocolates combine making the perfect cookie. This recipe will be on repeat in our house!
Nadia says
My new favorite cookie! It's so delicious and the recipe is so easy to follow, perfect for Halloween too!
Kayla says
Thanks Nadia!! I'm glad you enjoyed them so much! 🙂
Sweetsobsessedolga says
This recipe is seriously awesome. I chilled the dough for an hour because I like thicker cookies, and they turned out so thick with chewy edges and super soft centers full of creamy peanut butter, healthy oats, colorful M&Ms and gooey chocolate chips - my dream cookie basically. Highly recommend this recipe! A must try for all my fellow cookie monsters.
Kayla says
Chilling the dough is such a pro cookie monster move!! 🙂 thank you for trying my recipe, Olga! So glad you liked them!
Tess Stecklein says
These cookies were amazing! As someone who hasn’t baked in years, Kayla’s recipe was easy to follow and these cookies were simple to make (even without a mixer)! The taste and texture were both wonderful, and we literally could not stop eating them! From the cookie dough, to fresh out of the oven, to a few days post-baking, every time these monster cookies hit the spot! I cannot say enough great things about these cookies and I will be making these again soon!
Kayla says
Hey Tess, I'm honored that you broke your no-baking streak with my monster cookies and I'm so glad you enjoyed them! Thanks so much for trying my recipe!
Liz says
Okay, these are actually scary good. The peanut butter and oats and m&ms all combine so perfectly. These were so easy to make which is a good thing because once I started eating them, I couldn't stop! I'll be making these for gifts and cookie swaps and basically any excuse I can find!
Kayla says
Thanks Liz, I’m SO glad you enjoyed them!!
AJ says
I wanted to make this recioe for years and found rhis recipe. The cookies exceeded my expecrationa. It is a yummy combination of salty and sweet. The oats give the cookies a rich texture and they are super moist. I made a larger cookie so they were perfect for an ice cream sandwich with vanilla bean ice cream. These are now added to my cookie recipes.
AJ says
I wanted to make this recioe for years and found rhis recipe. The cookies exceeded my expecrationa. It is a yummy combination of salty and sweet. The oats give the cookies a rich texture and they are super moist. I made a larger cookie so they were perfect for an ice cream sandwich with vanilla bean ice cream. These are now added to my cookie recipes.
Kayla says
Hi AJ! Thank you for trying my recipe, I'm thrilled that you loved them so much that they made it onto your cookie list! Ice cream sandwiches were such a great idea!