Monster Cookie Fudgy Brownies – Fun, Spooky, and Fudgy Dessert for Parties
If there’s one treat that perfectly balances the chaos of Halloween and the indulgence of chocolate, it’s Monster Cookie Fudgy Brownies. These brownies aren’t just ordinary chocolate treats—they combine the chewy, fudgy goodness of a brownie with the playful chaos of a monster cookie. Imagine gooey chocolate, chunks of peanut butter, colorful candy-coated chocolate pieces, and a slightly chewy cookie texture all in one bite. This recipe is perfect for parties, dessert tables, or a fun weekend baking activity with kids.

Why Monster Cookie Fudgy Brownies Are a Must-Try
Brownies have always been a crowd favorite, but combining them with monster cookies elevates them to another level. Not only do you get a chewy chocolate base, but the cookie pieces provide a textural contrast that makes every bite exciting. Plus, the colorful candies on top give a festive, Halloween-ready look without much effort. It’s a versatile recipe: serve it at birthday parties, bake sales, or even as a playful weekday dessert.
These brownies are easy to make, requiring no special skills. Whether you’re a seasoned baker or a beginner, you can whip them up in less than an hour. And because they’re made in a single pan, cleanup is minimal—always a bonus!
Ingredients
- Brownie Base
- 1 cup unsalted butter, melted
- 2 cups granulated sugar
- 4 large eggs
- 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 colorful candy-coated chocolate
- 0.5 cup chopped walnuts (optional)

Instructions
- Preheat your oven to 350°F (175°C) and line a 9×13-inch baking pan with parchment paper. Lightly grease the edges.
- In a large mixing bowl, combine melted butter and sugar until smooth. Stir in the eggs one at a time, then mix in vanilla extract.
- In a separate bowl, whisk together flour, cocoa powder, and salt. Gradually fold into the wet ingredients until fully incorporated.
- Add rolled oats, peanut butter chips, chocolate chips, M&Ms, and walnuts (if using). Stir gently to evenly distribute mix-ins.
- Pour the batter into the prepared pan, smoothing the top with a spatula. Sprinkle a few extra M&Ms on top for decoration.
- Bake for 30–35 minutes, or until a toothpick inserted in the center comes out mostly clean but slightly fudgy. Avoid overbaking to keep them gooey.
- Allow brownies to cool completely in the pan before cutting into squares. Serve and watch the party guests go crazy for these colorful, fudgy treats!

Monster Cookie Fudgy Brownies
Ingredients
Equipment
Method
- Preheat oven to 350°F (175°C) and line a 9×13-inch pan with parchment paper.
- Combine melted butter and sugar until smooth. Stir in eggs and vanilla extract.
- Whisk together flour, cocoa powder, and salt. Gradually fold into wet ingredients.
- Add oats, peanut butter chips, chocolate chips, M&Ms, and walnuts. Fold gently.
- Pour batter into pan, smooth top, sprinkle extra M&Ms.
- Bake 30–35 minutes, until toothpick comes out mostly clean. Cool completely before cutting.
Notes
Tips for Perfect Monster Cookie Fudgy Brownies
- Don’t overmix: Overmixing the batter can make the brownies tough. Fold in the mix-ins gently.
- Customize the candy: Swap M&Ms for Reese’s Pieces or even Halloween-themed candy for a seasonal twist.
- Make ahead: These brownies stay fresh for up to 4 days at room temperature or can be frozen for up to 3 months.
- Serving idea: Pair with a scoop of vanilla ice cream for an extra indulgent dessert experience.
These Monster Cookie Fudgy Brownies aren’t just a dessert—they’re an experience. The mix of textures and colors makes them perfect for parties or any festive occasion. Kids love them, adults love them, and they’re a guaranteed crowd-pleaser at Halloween or anytime you want to add a little fun to your dessert table.