Monster Cookie Fudgy Brownies are the ultimate dessert mashup: rich, gooey chocolate brownies layered with peanut butter, oats, colorful candies, and chocolate chips. Every bite is a decadent, chewy explosion of flavor and texture — just like your favorite monster cookie, only more indulgent.
Perfect for parties, bake sales, or a cozy night in, these brownies combine the best of cookies and brownies in one mouthwatering treat.
Why You’ll Love Monster Cookie Fudgy Brownies
- Thick, soft, and intensely fudgy
- Loaded with mix-ins: oats, chocolate chips, peanut butter, and M&M-style candies
- Easy to make in one pan
- Perfect for slicing and sharing
- Customizable with your favorite add-ins
Ingredients
For the Brownie Base:
- 1/2 cup unsalted butter (melted)
- 1 cup granulated sugar
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/3 cup cocoa powder
- 1/2 cup all-purpose flour
- 1/4 teaspoon salt
- 1/2 cup semi-sweet chocolate chips
For the Monster Cookie Layer:
- 1/2 cup creamy peanut butter
- 1/4 cup unsalted butter (softened)
- 1/2 cup brown sugar
- 1 egg
- 1/2 teaspoon vanilla extract
- 3/4 cup all-purpose flour
- 1/4 teaspoon baking soda
- 1/4 teaspoon salt
- 1/2 cup quick oats
- 1/3 cup mini chocolate chips
- 1/3 cup candy-coated chocolate pieces (like M&M’s)
How to Make Monster Cookie Fudgy Brownies
Step 1: Make the Brownie Batter
In a bowl, mix melted butter and sugar. Add eggs and vanilla, then stir in cocoa powder, flour, and salt until combined. Fold in chocolate chips.
Pour into a greased or parchment-lined 9×9-inch baking pan.
Step 2: Make the Monster Cookie Dough
In another bowl, cream peanut butter, butter, and brown sugar. Add egg and vanilla. Stir in flour, baking soda, and salt. Mix in oats, chocolate chips, and candies.
Drop spoonfuls of cookie dough over the brownie layer and gently spread to cover most of the top. Don’t worry about perfection — swirls and chunks are welcome!
Step 3: Bake
Bake at 350°F (175°C) for 30–35 minutes or until edges are set and center is just slightly jiggly. Cool completely before slicing.
Tips for Perfect Monster Brownies
- Use parchment for easy removal
- Let them cool before cutting for clean slices
- Chill for 30 minutes before slicing if needed
- Don’t overbake — center should be fudgy
- Use colorful candies for a festive look
Fun Variations
Nut-Free Version
Swap peanut butter for sunflower seed butter or almond butter.
Holiday Style
Use red and green candies for Christmas or pastel colors for Easter.
Add More Mix-Ins
Try chopped pretzels, marshmallows, or toffee bits.
Double Chocolate
Add cocoa powder or chocolate chunks to the cookie dough.
Gluten-Free
Use a 1:1 gluten-free flour blend and certified GF oats.
Serving Suggestions
- Pair with a scoop of vanilla or peanut butter ice cream
- Serve with cold milk or hot cocoa
- Cut into mini squares for party trays
- Stack and wrap in parchment for edible gifts
Storage & Freezing
- Room Temperature: Store in airtight container up to 4 days
- Fridge: Keeps well up to 7 days
- Freezer: Freeze sliced brownies for up to 2 months
- Reheat: Microwave 10 seconds for extra gooeyness
Nutrition Info (Per Brownie)
| Nutrient | Amount |
|---|---|
| Calories | 280 kcal |
| Protein | 4 g |
| Carbohydrates | 34 g |
| Fat | 15 g |
| Sugar | 20 g |
| Sodium | 120 mg |
Frequently Asked Questions
Can I make these without peanut butter?
Yes, substitute with almond butter or leave it out and adjust the flour slightly. The flavor and texture will vary.
Do I need to chill the dough?
No chilling required. The dough spreads nicely right after mixing.
Can I make these in a larger pan?
Yes, but the bars will be thinner. Reduce baking time accordingly and check for doneness early.
Can I use store-bought brownie mix?
Yes! Prepare according to package instructions and layer with homemade monster cookie dough.
Are these freezer-friendly?
Absolutely. Wrap individually and freeze for quick snacks or dessert prep.
Final Thoughts
Monster Cookie Fudgy Brownies are the perfect combo of chewy cookie and decadent brownie — rich, colorful, and loaded with all your favorite mix-ins. Whether you bake them for a party, treat yourself, or pack them in a lunchbox, these brownies are guaranteed to steal the show.
One pan, two desserts, and endless smiles. These will become a go-to in your baking rotation!
Monster Cookie Fudgy Brownies
Ingredients
Brownie Base
- 113 g unsalted butter (melted)
- 200 g granulated sugar
- 2 large eggs
- 1 tsp vanilla extract
- 35 g cocoa powder
- 60 g all-purpose flour
- 0.25 tsp salt
- 90 g semi-sweet chocolate chips
Monster Cookie Layer
- 120 g creamy peanut butter
- 57 g unsalted butter (softened)
- 100 g brown sugar
- 1 egg
- 0.5 tsp vanilla extract
- 90 g all-purpose flour
- 0.25 tsp baking soda
- 0.25 tsp salt
- 45 g quick oats
- 60 g mini chocolate chips
- 60 g candy-coated chocolate pieces (like M&M’s)
Instructions
- Step 1: Make the Brownie Batter
In a bowl, mix melted butter and sugar. Add eggs and vanilla, then stir in cocoa powder, flour, and salt until combined. Fold in chocolate chips. Pour into a greased or parchment-lined 9×9-inch baking pan. - Step 2: Make the Monster Cookie Dough
In another bowl, cream peanut butter, butter, and brown sugar. Add egg and vanilla. Stir in flour, baking soda, and salt. Mix in oats, chocolate chips, and candies. - Step 3: Layer and Bake
Drop spoonfuls of the cookie dough over the brownie batter and gently spread to cover most of the top. Bake at 350°F (175°C) for 30–35 minutes or until edges are set and center is slightly jiggly. Cool completely before slicing.
Notes
• Nut-free: Use sunflower seed butter instead of peanut butter.
• Holiday version: Use seasonal candy colors.
• Extra indulgent: Add chopped pretzels or marshmallows.
• Gluten-free: Use GF flour and oats. Serving Suggestions:
Serve with ice cream, milk, or hot cocoa. Cut into mini squares for parties or wrap for gifts. Storage:
Room temp up to 4 days. Fridge up to 7 days. Freeze up to 2 months. Microwave 10 seconds to reheat.