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These Thick and Chewy Monster Cookies are loaded with peanut butter, oats, M&M's and chocolate chips. They’re a cross between a chewy oatmeal chocolate chip cookie, and a peanut butter cookie, and they’re sure to be a huge hit with family and friends.
I LOVE making cookies, and since I don't usually have fresh-baked cookies available on the spot, I like to freeze them for when friends come over or when we just want a little treat. In my freezer currently are Jumbo Chocolate Chip Cookies, Red Velvet Sandwich Cookies, and Chewy Pumpkin Chocolate Chip Cookies. Who wants to come over?!
Monster Cookies
Don't ask me to choose a favorite type of cookie because I just wouldn't be able to! There are too many fun variations. These Monster Cookies are always popular and I love the great texture from the oats and the subtle peanut butter flavor.
Why are they called Monster Cookies?
There’s not an exact answer for why these cookies are called “Monster” Cookies. Some people think it’s because they look like monsters, with their bumpy texture and fun colors. I like to think it’s because they’re stuffed with so much “stuff”, making them the “monster” of all cookies.
Whatever the reason, all Monster Cookies have these ingredients in common: peanut butter, oats, chocolate chips and m&m chocolate candy.
How to make Monster Cookies:
- Cream the butter and sugars. Use REAL butter and cream it with the sugar for at least 2-3 minutes until really light and fluffy. This is adding air to the mixture and is the base for the texture we want in our cookies.
- Mix wet ingredients. Add the peanut butter and mix well. Add egg and vanilla and mix.
- Measure flour properly and mix dry ingredients. When measuring the flour be sure to fluff it a bit first, allowing air to fill in (like sifting) before you spoon it lightly into the measuring cup. Stir together the flour, oats, salt, baking powder and baking soda. Stir into wet mixture with m&m's and chocolate chips.
- Slightly under-bake. Bake at 350, being careful not to over bake the monster cookies. The tops will look just set and they will continue to harden and set up as they cool on the baking sheet.
How do I keep my cookies from spreading?
During baking, cookies naturally spread, but the key is to make sure they don't spread too much. To keep your monster cookies from spreading, be sure to use exact measurements (no guesstimating) and use room temperature ingredients, particularly the butter and eggs. You can also stop cookies from getting flat by chilling the dough for 15-30 minutes before baking.
Storage and Freezing Instructions:
These cookies will keep well in an air-tight container for 1-2 days, or you can freeze the cookie dough or baked cookies. To freeze them after they’re baked, allow them to cool completely and store them in a freezer safe container for up to 3 months. Freeze cookie dough balls in a freezer safe container and when ready to bake, place the frozen cookie dough on a baking sheet and add 2-4 minutes to the baking time.
CONSIDER TRYING THESE POPULAR COOKIE RECIPES:
- Jumbo Chocolate Chip Cookies
- Super Soft Sugar Cookies
- Triple Chip Blondies
- M&M Cookie Bars
- Chocolate Mint Cookies
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Thick and Chewy Monster Cookies
Equipment
- Stand Mixer optional
Ingredients
- 1/2 cup butter
- 1/2 cup granulated sugar
- 1/2 cup light brown sugar
- 1/2 cup peanut butter
- 1 egg
- 1 teaspoon vanilla extract
- 1 cup all-purpose flour
- 1 1/4 cups old-fashioned rolled oats
- 1/4 teaspoon salt
- 1/2 teaspoon baking powder
- 1/2 teaspoon baking soda
- 3/4 cup M&M candies
- 1/2 cup semi-sweet chocolate chips
Instructions
- Preheat oven to 350 degrees F.
- Cream the butter and sugar together really well—at least 2-3 minutes until light and fluffy.
- Add peanut butter and mix well. Add egg and vanilla and mix.
- In a separate mixing bowl stir together the flour (be careful to measure correctly, spooning the flour into a measuring cup, then leveling off), oats, salt, baking powder and baking soda.
- Add to the wet mixture and mix to combine. Stir in chocolate chips and M&M’s.
- Bake at 350 degrees for 10-12 minutes, or a little longer if you make them bigger than a 1 inch cookie scoop. Don't over bake--they will look just set.
- Remove them from the oven and allow them to cool completely on the pan.
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
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HAVE YOU TRIED THIS RECIPE?!
RATE and COMMENT below! I would love to hear your experience.
OMG, these cookies are to die for. 10/10 would recommend. the only part I regret is eating them all. haha 😅
How many tablespoons per cookie?? I wish she would clarify the instructions.
I’m so sad I didn’t bake a double batch 😭
I should have never made these cookies because they are so so delicious and I will eat them all!!
Every year I do a “bake off” where I try several recipes of the same type of cookie. This year was monster cookies, and this came out the winner! Best of the top four recipes on the internet. Thanks for sharing!
BEST MONSTER COOKIES EVER! They’re crisp on the outside and chewy on the inside. We used the pack of M&M’s with peanut, peanut butter, and regular in it and it was a great choice.
I love monster cookies so much and these are delicious. Nice and chewy they don’t get hard if they sit out or in the fridge. They’re literally perfect.
I have made this recipe so many times and decided it was time to comment. These are the best monster cookies. thank you. we make them all the time.
The cookie dough is delicious and so are the cookies. However, my cookies did not spread at all and came out as round balls. I creamed the sugars with the butter and the egg, then added the vanilla and peanut butter. I also used Quick Oats. I used a 1-in cookie scoop to place them on a parchment paper lined cookie sheet and baked them for 12 minutes at 350°. Puzzled as to why they came out of the oven the same shape as they went in. 🤔
Mine did too, and they were HARD! It was very tasty, though, so next time I might add more butter.
I actually liked that they didn’t spread. I forgot to flatten one batch and they were a little rounder but I liked them that way.
My guess is that there might be too much flour or the butter was too cold. Try adding less flour or warmer butter!
Great light cookie. I didnt’ add any chocolate except 3 chocolate 3 chocolate mini eggs on top and was a hit. The cookies were so easy to break apart you had to be careful was my only problem, but that was okay. Maybe the chocolate added would have bonded it better which as I said I didn’t do. Good cookie
too sweet
I made one batch without chocolate and added walnuts. They were less sweet and friends liked that about them.
Made these for the first time with my granddaughters. They loved them. This recipe is a keeper!
Hi Lauren. Last weekend I made these cookies for the first time. And lucky for me I had my 2 grandsons age 2 and 4 to help !! The cookies turned out so well and they were delicious. Thank you so much for sharing this recipe with everyone. It was very easy to follow. I can’t wait to try more of your recipes. Your an expert for sure ♥️
This recipe is makes a super crumbly cookie that falls apart. I’ll definitely be trying a different recipe next time.
Followed recipe to a T, taste is good, but they are falling apart very hard to remove from pan let alone eat. Disappointed.
I waited for them to cool before removing and that was the key to not falling apart.
These cookies are SO FREAKING DELICIOUS. I’ve made them twice now, and every single time they turn out perfectly. I use cold butter instead of room temp so that they don’t spread, and follow everything else to the letter. Make these now, don’t wait, they will blow your mind.
The cookies came out great. I make these for my grandchildren and they really enjoy them.
I love the texture compared to normal cookies. Great dipping cookie.
It is common sense but it does not mention to soften the butter. The cookies did not spread well and the oats in this were hard to chew through, this maybe have been my oats. I also think it could have a little more salt. Overall, I think these are OK, not my favorite, but worth a try.