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Monster Cookie Fudgy Brownies Recipe

4.7 from 97 reviews

Delight in these Monster Cookie Fudgy Brownies, a decadent fusion of rich, fudgy chocolate brownies topped with classic monster cookie dough featuring oats, M&M’s, and chocolate chips. This indulgent dessert combines the gooey texture of brownies with the chewy, colorful crunch of monster cookies for a unique treat perfect for any occasion.

Ingredients

Scale

Monster Cookie Dough

  • 1/2 cup All-purpose flour
  • 1 tsp Cornstarch
  • 1/2 tsp Baking soda
  • 1/8 tsp Baking powder
  • 1/4 tsp Salt
  • 1/4 cup Unsalted butter (room temperature)
  • 1/3 cup Brown sugar (packed light or dark)
  • 1/8 cup White granulated sugar
  • 1/4 cup Peanut butter (creamy)
  • 1 tsp Pure vanilla extract
  • 1 Large egg (room temperature)
  • 1/2 cup Quick oats
  • 1/2 cup Mini chocolate chips
  • 1/2 cup Mini M&M’s

Brownie Batter

  • 1 1/3 cup White granulated sugar
  • 2 Large eggs
  • 1 Egg yolk
  • 5 TBSP Unsalted butter
  • 1/3 cup Oil (canola or vegetable)
  • 1 tsp Pure vanilla extract
  • 1/2 cup All-purpose flour
  • 3/4 cup Unsweetened cocoa powder (Dutch process)
  • 1 TBSP Cornstarch
  • 1/4 tsp Salt
  • 1/2 cup Semi-sweet chocolate chips
  • 1/2 cup Milk chocolate chips

Instructions

  1. Prepare Monster Cookie Dry Ingredients: In a medium mixing bowl, combine 1/2 cup flour, 1 tsp cornstarch, 1/2 tsp baking soda, 1/8 tsp baking powder, and 1/4 tsp salt. Mix well to evenly distribute the leavening agents.
  2. Cream Butter and Sugars: Using a mixer, beat 1/4 cup room-temperature unsalted butter with 1/3 cup packed brown sugar and 1/8 cup white sugar on medium speed for 1 minute until light and fluffy. This aeration helps make the cookies tender.
  3. Add Peanut Butter: Mix in 1/4 cup creamy peanut butter and continue beating for another minute until fully combined and smooth.
  4. Incorporate Vanilla and Egg: Add 1 tsp pure vanilla extract and 1 large room-temperature egg to the mixture. Mix until combined, then scrape down the bowl sides and mix again for 20 seconds to ensure an even blend.
  5. Add Dry Ingredients and Mix-ins: Slowly add the dry flour mixture into the wet ingredients. Gently fold in 1/2 cup quick oats, 1/2 cup mini M&M’s, and 1/2 cup mini chocolate chips until just combined. Cover the dough and chill in the refrigerator for 40 minutes to firm up.
  6. Preheat Oven and Prepare Pan: About 10 minutes before finishing cookie dough chill time, preheat oven to 325°F (163°C). Spray a 9×9-inch baking pan with non-stick spray and line the bottom and two sides with parchment paper to help remove the brownies easily later.
  7. Prepare Brownie Dry Ingredients: In a separate medium bowl, whisk together 1/2 cup flour, 3/4 cup Dutch process cocoa powder, 1 tablespoon cornstarch, and 1/4 teaspoon salt. Set aside.
  8. Mix Brownie Wet Ingredients: Using a mixer with a whisk attachment, beat 1 1/3 cups white sugar, 2 large eggs, and 1 egg yolk for about 5 minutes until very light and fluffy. Meanwhile, melt 5 tablespoons unsalted butter and allow it to cool slightly.
  9. Add Butter, Oil, and Vanilla: Slowly add melted butter, 1/3 cup oil (canola or vegetable), and 1 tsp vanilla extract to the egg mixture on low speed until combined.
  10. Combine Dry and Wet Ingredients: Remove the mixture from the mixer and gently fold in the dry ingredients with a rubber spatula to retain the airiness. Add 1/2 cup semi-sweet chocolate chips and 1/2 cup milk chocolate chips, folding until evenly dispersed.
  11. Pour Brownie Batter Into Pan: Spread the batter evenly into the prepared baking pan and smooth the surface with a spatula.
  12. Initial Bake: Bake the brownie base for 15 minutes, just until the top is slightly set but still soft.
  13. Top With Cookie Dough: Remove the cookie dough from the fridge. Take small handfuls and flatten each into disc shapes. Place these cookie dough discs evenly on top of the partially baked brownie layer until all dough is used.
  14. Second Bake: Return the pan to the oven. Bake another 20 minutes. Then, loosely cover the top with foil to prevent over-browning and continue baking for an additional 5-10 minutes, or until the cookie topping and brownie are fully set with no jiggle.
  15. Cool Completely: Remove from oven and place the pan on a cooling rack. Allow the brownies to cool fully to room temperature before slicing to ensure clean cuts and set texture.
  16. Store: Store finished brownies at room temperature in an airtight container to maintain freshness.

Notes

  • Chilling the cookie dough before topping helps prevent it from melting into the brownies during baking.
  • Line and spray the baking pan well for easy removal and clean edges.
  • Use room temperature eggs and butter to ensure smooth blending and better texture.
  • Mixing the brownie batter gently after adding dry ingredients preserves air for a fudgier outcome.
  • Do not overbake; brownies should be set but moist inside for the perfect fudgy texture.
  • Allow the brownies to cool fully before cutting to avoid crumbling.

Keywords: monster cookie brownies, fudgy brownies, cookie dough brownies, chocolate brownie recipe, monster cookies