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Monster Cookie Fudgy Brownies

Fudgy chocolate brownies loaded with monster cookie mix-ins like peanut butter chips, chocolate chips, oats, and colorful candies. Perfect for Halloween or party treats.
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Prep Time 20 minutes
Cook Time 35 minutes
Total Time 55 minutes
Servings: 12 brownies
Course: Dessert, Snack
Cuisine: American
Calories: 320
Ingredients Equipment Method Notes

Ingredients
  

Brownie Base
  • 1 cup unsalted butter melted
  • 2 cups granulated sugar
  • 4 eggs large
  • 1 tsp vanilla extract
  • 1 cup all-purpose flour
  • 1 cup unsweetened cocoa powder
  • 0.5 tsp salt
Monster Cookie Mix-In
  • 1 cup rolled oats
  • 1 cup peanut butter chips
  • 1 cup chocolate chips
  • 1 cup M&Ms or candy-coated chocolate
  • 0.5 cup chopped walnuts optional

Equipment

  • Mixing bowls
  • 9x13 inch baking pan
  • Spatula

Method
 

  1. Preheat oven to 350°F (175°C) and line a 9x13-inch pan with parchment paper.
  2. Combine melted butter and sugar until smooth. Stir in eggs and vanilla extract.
  3. Whisk together flour, cocoa powder, and salt. Gradually fold into wet ingredients.
  4. Add oats, peanut butter chips, chocolate chips, M&Ms, and walnuts. Fold gently.
  5. Pour batter into pan, smooth top, sprinkle extra M&Ms.
  6. Bake 30–35 minutes, until toothpick comes out mostly clean. Cool completely before cutting.

Notes

Customize with seasonal candy or pair with ice cream. Store at room temperature for up to 4 days.