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The Best Monster Cookies | Monster Cookies | Cookies | The best monster cookies are loaded with peanut butter, oats, chocolate chips, and m&m's! They are thick, chewy, and a soft-baked cookie, with a surprise ingredient, that are addictive and delicious. #cookies #dessert #dessertrecipes #thebestrecipes

The Best Monster Cookies

The Best Monster Cookies are loaded with peanut butter, oats, chocolate chips, and m&m's! They are thick, chewy, and a soft-baked cookie, with a surprise ingredient, that are crazy delicious.
Course Dessert
Cuisine American
Keyword cookies, monster cookie recipe, monster cookies, the best monster cookies
Prep Time 15 minutes
Cook Time 8 minutes
Total Time 23 minutes
Servings 30 cookies
Calories 190kcal
Author Jessica


  • 1/2 cup butter softened
  • 1 cup brown sugar
  • 1/2 cup creamy peanut butter
  • 1 large egg
  • 2 teaspoons vanilla extract
  • 3/4 cup all-purpose flour
  • 1 teaspoon baking soda
  • 1 teaspoon cornstarch
  • 1/4 teaspoon baking powder
  • 1/4 teaspoon salt
  • 1 1/2 cups quick oats
  • 1 cup mini semi-sweet chocolate chips
  • 1 cup mini M&M candies


  • Preheat oven to 350 degrees. Line cookie sheets with parchment paper or use a silpat liner.
  • In a large bowl (or bowl of a stand mixer) cream together the butter, brown sugar, and peanut butter until light and fluffy, about 2-3 minutes.
  • Mix in the egg and vanilla, scraping down the sides of the bowl as needed.
  • In a separate bowl, add the flour, baking soda, cornstarch, baking powder, and salt and whisk to combine.
  • With the mixer on low speed, slowly add the flour mixture to the wet ingredients and mix until just combined.
  • Add the oats, chocolate chips, and M&M candies. Mix on low speed just until dough is combined.
  • Use a small/medium cookie scoop, or about 1-2 tablespoons cookie dough, and place on the baking sheets. They should look like golf balls. 
  • Bake the cookies for 7-9 minutes until the edges are just starting to brown and the top still looks slightly undercooked.
  • Remove from the oven and cool for 5 minutes on the baking sheet before moving them to a wire rack to cool completely.
  • ** For more of a cookie shape, take the bottom of a glass cup and gently press down on the cookie a few minutes after they come out of the oven OR just press some additional m&m's on tops of the cooked cookies and that will naturally press them down into more of a cookie shape, I always do this and it works so well. The cookies don't spread much at all while baking. 



Natural peanut butter does not work well in this recipe.
Press some additional m&m's on top of the cookie dough balls, before putting cookie sheet in the oven, for a pretty presentation. Or press some m&m's on top of the cookies after they come out of the oven to naturally press down the cookies into more of a cookie sheet. Hard to explain in words, but if you try it, you'll know what I mean. 
Use the bottom of a glass cup to gently press the cookie down when you take them out of the oven. Or leave as is for a puffy, round cookie.
I have also made giant monster cookies. Form 1/4 cup of dough into a ball and then slightly flatten on the cookie sheet. Bake for about 11-13 minutes.
2-3 minutes will seem like a long time to mix the sugars, peanut butter, and butter but it's really important to do it for about that long. The dough will be much lighter in color and look fluffy. That's when you know you have blended it long enough.
I prefer to use salted butter.


Calories: 190kcal | Carbohydrates: 22g | Protein: 3g | Fat: 10g | Saturated Fat: 5g | Cholesterol: 15mg | Sodium: 112mg | Potassium: 105mg | Fiber: 2g | Sugar: 15g | Vitamin A: 122IU | Vitamin C: 1mg | Calcium: 26mg | Iron: 1mg