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A large monster cookie on a black drying rack.

Monster Cookies

Our Monster Cookies combine rich peanut butter with the sweet crunch of M&M’s and chocolate chips. Brown sugar and vanilla add depth, while old-fashioned oats provide a hearty chew. Perfect for any occasion, these cookies promise a delightful mix of flavors that will leave you craving more.

Yield: 28 cookies 1x
Prep: 10 minutesCook: 12 minutesTotal: 22 minutes


  • 1/2 cup butter (1 stick), softened
  • 1 1/2 cups peanut butter
  • 1 cup brown sugar
  • 1 cup white sugar
  • 2 teaspoons baking soda
  • 3 eggs
  • 2 teaspoons vanilla
  • 1 cup M&M’s
  • 1 cup chocolate chips
  • 4 1/2 cups old-fashioned oats (Quick oats will work in a pinch.)

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  1. Preheat the oven to 325°F and line two large baking sheets with parchment paper (or spray the sheet pans with cooking spray).
  2. In a large mixing bowl combine butter, peanut butter, brown sugar, white sugar, baking soda, eggs, and vanilla. Stir until well combined.
  3. Stir in the M&Ms, chocolate chips, and the oats.
  4. Using a 1/4 measuring cup to scoop dough onto lined baking sheets.
  5. Bake for 10-12 minutes (depending on size). They will appear a tad gooey but that’s ok!
  6. Let cookies cool for at least 30 minutes on baking sheets before removing them. 


  • You must let them cool down for at least 30 minutes before eating.
  • Do not over bake. They will look undercooked at 10-12 minutes but take them out anyway!
  • While oats are naturally gluten-free, oftentimes they’re processed in a factory where cross-contamination can happen. Look for a “certified gluten-free” label on your oats, if avoiding all gluten is important to you.
  • While it’s tempting, don’t worry about pressing the dough the down after scooping. They’ll flatten out on their own. 
© Author: Polly Conner
Cuisine: American Method: Bake