Go Back

Monster Cookies

Monster cookies made with thick, chewy peanut butter cookie dough loaded with M&Ms, chocolate chips, and visible oats. Baked until golden-edged with soft, slightly underdone centers for that gooey bake-through texture.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 12 minutes
Total Time 27 minutes
Servings: 24 servings
Course: Dessert
Cuisine: American
Calories: 240
Ingredients Equipment Method Notes

Ingredients
  

Peanut butter cookie base
  • 1.5 cup creamy peanut butter Use creamy style for best chewy texture.
  • 1 cup brown sugar, packed Pack firmly for deeper caramel flavor.
  • 0.5 cup granulated sugar
  • 3 large eggs
  • 2 tsp vanilla extract
  • 1 tsp baking soda
  • 3 cup quick-cooking oats Quick-cooking oats keep the cookie tender and chewy.
  • 1 cup M&Ms (red, white, and blue for patriotic version) Use a full-color mix for colorful bites.
  • 0.5 cup chocolate chips
  • 0.5 cup mini chocolate chips

Equipment

  • 1 sheet pan

Method
 

Preheat and prep
  1. Preheat oven to 350°F and line two baking sheets with parchment paper, so the cookies bake evenly and release easily.
Mix the dough
  1. Beat creamy peanut butter, brown sugar, and granulated sugar together until combined and smooth.
  2. Add large eggs, vanilla extract, and baking soda, then mix until smooth and uniform.
  3. Stir in quick-cooking oats until fully incorporated, keeping the dough thick with visible oats.
  4. Fold in M&Ms (red, white, and blue for patriotic version) and chocolate chips until every portion is loaded with mix-ins.
Scoop, bake, and cool
  1. Scoop dough into 2-tablespoon balls and place 2 inches apart on the prepared baking sheets, flattening slightly with your palm.
  2. Bake for 10–12 minutes at 350°F until edges are set but centers still look slightly underdone for a soft center.
  3. Let cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack so they firm up as they cool.

Notes

Pro tip: For thicker, chewier cookies, keep the dough portion size consistent at 2 tablespoons and don’t overbake—look for set edges with slightly underdone centers. Store in an airtight container at room temperature for up to 5 days. Freeze baked cookies for up to 2 months (thaw at room temperature). For a gluten-free swap, use certified gluten-free oats.