Monster Cookies
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Get ready to indulge in these soft and chewy Monster Cookies! Packed to the brim with creamy peanut butter, hearty oats, colorful M&M’s, and rich chocolate chips, they’re the ultimate treat!

Imagine the perfect fusion of a chewy oatmeal chocolate chip cookie and a decadent peanut butter cookie. These monster cookies are guaranteed to be a hit with family and friends alike! Whether you’re sharing or keeping them all to yourself (I won’t judge ), these cookies will make your taste buds dance.
Ingredients
For the ingredient measurements and the entire recipe, be sure to scroll down to the bottom of the blog post where the recipe card is located.
- Oats: Old-fashioned rolled oats work best!
- Peanut Butter: Use commercial brand creamy peanut butter for the best results.
- Baking soda
- Salt
- Flour: All-purpose flour works with the oats to create a soft, chewy texture.
- Sugar: Both granulated and brown sugar are used. You can use light or dark brown sugar.
- Egg
- Vanilla: As always, choose a high-quality pure vanilla for the very best flavor.
- Mix-ins: Monster cookies are known for their chocolate chips and M&M’s.

Step by Step Directions
For the full recipe instructions, scroll down to the bottom of the blog post to the recipe card.
- Combine the wet ingredients. Mix the butter, peanut butter, and both sugars until well combined. Mix in the vanilla and egg.
- Combine the dry ingredients. Whisk the oats, flour, baking soda, and salt together in bowl.
- Combine the wet and dry ingredients. Add the oat mixture to the peanut butter mixture and mix just until combined.
- Add mix-ins. Stir in the M&M’s and chocolate chips.
- Bake. Portion the dough with a 1.5 tablespoons scoop and bake for 10-12 minutes.




Tips For Success
- Oats: Be sure to use old-fashioned oats. Quick oats will not work the same in this recipe.
- Prevent cookies from spreading too much during baking by using exact measurements. I highly recommend a digital kitchen scale for this.
- Avoid natural peanut butters, they tend to be too oily. Commercial brand creamy peanut butter will work best for monster cookies.

More Recipes You’ll Love
- Old Fashioned Oatmeal Raisin Cookies
- Oatmeal Chocolate Chip Cookies
- Oatmeal Scotchies
- Apple Oatmeal Cookies
Monster Cookies

Ingredients
- 1 ½ cups (148 g) old fashioned rolled oats
- ½ cup (65 g) all-purpose flour
- ½ teaspoon baking soda
- ¼ teaspoon salt
- ½ cup (113 g) unsalted butter, at room temperature
- ½ cup (135 g) creamy peanut butter
- ½ cup (100 g) granulated sugar
- ½ cup (100 g) light brown sugar, packed
- 1 large egg, at room temperature
- 1 teaspoon vanilla extract
- ½ cup (85 g) semisweet chocolate chips
- ½ cup (100 g) M&M candies
Instructions
- Preheat the oven to 350℉ and line 2 baking sheets with parchment paper.
- In a medium bowl, whisk the oats, flour, baking soda, and salt together.
- Using a stand mixer fitted with the paddle or with a handheld electric mixer and large bowl, beat the butter, peanut butter, and both sugars until light and fluffy, about 2 minutes.
- Beat in the egg and vanilla.
- Add the oat mixture, and mix on low speed just until combined.
- Fold in the chocolate chips and M&M's with a silicone spatula.
- Using a 1 ½ tablespoon cookie scoop place mounds of dough 2 inches apart onto the prepared baking sheets.
- Bake cookies for 10-12 minutes until the edges are slightly browned. Cool on the pan for 5 minutes, then transfer to a wire rack to cool completely.
Notes
Nutrition
The nutrition information provided is for convenience and as a courtesy only. It is not guaranteed to be accurate because nutrition information can vary for a variety of reasons. For precise nutritional data use your preferred nutrition calculator and input the exact ingredients and brands you used in the recipe.