Monster Cookies
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Our Monster Cookies combine rich peanut butter with the sweet crunch of M&M’s and chocolate chips. Brown sugar and vanilla add depth, while old-fashioned oats provide a hearty chew. Perfect for any occasion, these cookies promise a delightful mix of flavors that will leave you craving more.
Why You’ll Love this Recipe
- Packed with Flavor: Monster cookies blend rich peanut butter, sweet chocolate, and smooth vanilla, creating a mouthwatering cookie.
- Texture Variety: The combination of old-fashioned oats, crunchy M&M’s, and melty chocolate chips provides a satisfying mix of textures in every bite.
- Versatile and Convenient: Whether you use old-fashioned or quick oats, these cookies are easy to make and adaptable to your pantry ingredients.
- Crowd-Pleasers: Perfect for any occasion, from bake sales to family gatherings, these cookies are a guaranteed hit with both kids and adults.
- Hearty and Satisfying: Jam packed with peanut butter and oats, monster cookies are a filling treat that satisfies even the biggest sweet tooth.
Ingredients
What’s interesting to me about these Monster Cookies is that there is no flour in the recipe. Nada. Just a lot of oats, peanut butter, and sugar. Here is what you’ll need:
Ingredient Notes:
- Old-fashioned oats – quick oats will work in a pinch
- M&M’s – I prefer mini but the full sized ones will work as well.
How to Make Monster Cookies
It’s super simple!
1. In a large mixing bowl combine butter, peanut butter, brown sugar, white sugar, baking soda, eggs, and vanilla. Stir until well combined.
2. After that, stir in 4 1/2 cups of old-fashioned oats. Not a typo. Lots of oats. Probably why the recipe can get away with no flour.
5. Use a cookie scoop or measuring cup, scoop out about 1/3 portions and plop them on the parchment lines baking sheet. Don’t press them down if you want them thick and gooey.
6. Bake for about 12 minutes. At 12 minutes you are going to think, “These don’t look done. That blogger is wrong. I need to cook these longer.”
Wrong, wrong, wrong. Take them out!
7. You must let them cool down for at least 30 minutes. If you try too early, they will fall apart and you will send curses my way. Patience, my friend.
They will be thick and gooey but shouldn’t fall apart when picked up.
Tip: Don’t press cookie dough balls down
Because it’s such a large portion of cookie dough, you’ll be tempted to press the cookie dough balls down before cooking.
There is no need for this! They will flatten out on their own. In the picture below, the 6 on the left side were not touched and the 6 on the right side were pressed down prior to cooking.
As you can see the cookies on the right side are flatter.
Recipe FAQs
If you try to avoid gluten in your diet, here’s the good news: Oats are naturally gluten-free. However, they are oftentimes processed in a factory where cross-contamination can happen. Look for a “certified gluten-free” label on your oats, if avoiding all gluten is important to you.
Yes, most cookie doughs freeze very well. Scoop or shape the dough, place on a baking sheet to flash freeze, then transfer to an airtight container or freezer bag. Freeze for up to 3 months. Bake straight from frozen—just add 1–2 minutes to the baking time.
Yes, baked cookies can be frozen for up to three months.
Cookies are often best stored at room temperature in an airtight container. Use layers of parchment paper if you need to layer the cookies.
Yes, you can make the dough in advance and refrigerate for up to 3 days or freeze it for up to 3 months.
More Delicious Cookies to Try
If you like these cookies, try one of our other yummy recipes.
How to Video
Monster Cookies
Ingredients
- 1/2 cup (1 stick) unsalted butter (softened)
- 1 1/2 cups peanut butter
- 1 cup brown sugar
- 1 cup white sugar
- 2 teaspoons baking soda
- 3 eggs
- 2 teaspoons vanilla
- 1 cup M&M’s
- 1 cup chocolate chips
- 4 1/2 cups old-fashioned oats (Quick oats will work in a pinch.)
Instructions
- Preheat the oven to 325°F and line two large baking sheets with parchment paper (or spray the sheet pans with cooking spray).
- In a large mixing bowl combine butter, peanut butter, brown sugar, white sugar, baking soda, eggs, and vanilla. Stir until well combined.
- Stir in the M&Ms, chocolate chips, and the oats.
- Using a 1/4 measuring cup to scoop dough onto lined baking sheets.
- Bake for 10-12 minutes (depending on size). They will appear a tad gooey but that’s ok!
- Let cookies cool for at least 30 minutes on baking sheets before removing them.
Freezer Instructions
Notes/Tips
- You must let them cool down for at least 30 minutes before eating.
- Do not over bake. They will look undercooked at 10-12 minutes but take them out anyway!
- While oats are naturally gluten-free, oftentimes they’re processed in a factory where cross-contamination can happen. Look for a “certified gluten-free” label on your oats, if avoiding all gluten is important to you.
- While it’s tempting, don’t worry about pressing the dough the down after scooping. They’ll flatten out on their own.
Nutrition
Big hit yesterday for the 4th! I used dark chocolate m&Ms (only the red and blue) and mini chocolate chips.
Yay! Such a fun 4th of July idea. Thanks for sharing, Cheri.
Everyone loves these!!! I have even gotten a request for these instead of a birthday cake from my son-in-law.
That’s a huge compliment. Love it! Thanks for taking the time to leave feedback, Diane.
I wanted a large, easy Christmas cookie recipe and this was it! They looked festive and tasted great. It was incovenient that I needed to leave them on the pan for 30 minutes because I couldn’t finish the recipe for almost two hours. Great for freezing though! Thanks!
Can I substitute a different nut butter?
We haven’t tested this recipe with a different nut butter, but I think you could do that consistency-wise. Almond butter may be too overpowering. Perhaps sunbutter or cashew butter would work better. We’d love to hear your results, if you try it.
Are these quick oats or old fashions oats?
Old fashioned. I’ll add that to the recipe right now. Thanks for the great question.
Whoo-wee these are sweet! I have made them twice. I made them once with 1/2 coconut sugar and loved them. 2 cups of can sugar was way too sweet for me and I love my sweets! These make a lot but would be fun for a party of to have on hand to give to a guest, neighbor, etc.
Thanks for the feedback and letting us know about your tweaks.
So excited I just found this recipe again for teacher appreciation week!
It’s a good one! So nice of you to make cookies for the teachers Marie.