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Monster cookie with peanut butter, oats, chocolate chips, and colorful M&M'S pieces

Monster Cookies Peanut Butter Oatmeal Cookies with M&M'S

Monster Cookies are chewy peanut butter oatmeal cookies packed with classic mix-ins and a hearty texture. They are a fun homemade dessert choice for gatherings, bake sales, or anytime you want a crowd-friendly cookie.
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Prep Time 15 minutes
Cook Time 12 minutes
Total Time 27 minutes
Servings: 36 cookies
Course: Dessert
Cuisine: American
Calories: 220
Ingredients Method Notes

Ingredients
  

Wet ingredients
  • 1 cup (226 g) unsalted butter, softened
  • 1 cup (200 g) granulated sugar
  • 1 cup (220 g) brown sugar
  • 1 cup (270 g) creamy peanut butter
  • 3 large eggs
  • 2 teaspoons vanilla extract
Dry ingredients
  • 2 1/2 cups (312 g) all-purpose flour
  • 2 teaspoons baking soda
  • 4 cups (360 g) rolled oats
Mix-ins
  • 1 cup (170 g) semi-sweet chocolate chips
  • 1 cup (200 g) colorful M&M'S
  • 1 cup (120 g) chopped nuts, optional
  • 1 cup (170 g) butterscotch chips, optional
  • 1 cup (170 g) peanut butter chips, optional

Method
 

Preparation
  1. Preheat the oven to 350°F / 175°C and prepare two baking sheets with parchment paper.
  2. Beat the softened butter, granulated sugar, and brown sugar together, then blend in the peanut butter, eggs, and vanilla extract until the mixture is smooth.
  3. Mix in the flour and baking soda until the dough comes together, being careful not to overmix.
  4. Stir in the rolled oats, semi-sweet chocolate chips, M&M'S, and any optional nuts, butterscotch chips, or peanut butter chips until evenly distributed.
  5. Portion the dough onto the prepared baking sheets, spacing each cookie about 2 inches apart.
Baking
  1. Bake the cookies for 10 to 12 minutes, until the edges are lightly golden.
  2. Leave the cookies on the baking sheets for 5 minutes, then move them to a wire rack and allow them to cool completely.

Notes

If the dough is too soft to handle, chill it for 15 to 30 minutes before scooping and baking to help limit spreading.