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Benjamin

Fluffernutter Brownies | Easy Peanut Butter & Marshmallow Treat

These Fluffernutter Brownies are the ultimate mash-up of decadent chocolate brownies, gooey marshmallow fluff, and creamy peanut butter swirls. Perfectly indulgent, this recipe takes your brownies to the next level with its irresistible layers of flavor. Whether it’s for a party, a bake sale, or a personal treat, these brownies will be an instant hit!
Prep Time 15 minutes
Total Time 1 hour 30 minutes
Servings: 12 –16 brownies
Course: Dessert
Cuisine: American

Ingredients
  

For the Brownie Base:
  • 1 cup 226g unsalted butter, melted
  • 1 1/4 cups 250g granulated sugar
  • 3/4 cup 150g light brown sugar, packed
  • 3 large eggs room temperature
  • 2 teaspoons vanilla extract
  • 3/4 cup 95g all-purpose flour
  • 1/2 cup 45g unsweetened cocoa powder
  • 1/2 teaspoon kosher salt
For the Fluffernutter Layer:
  • 1 cup creamy peanut butter
  • 1 1/2 cups marshmallow fluff or cream

Method
 

Preheat the Oven:
  1. Preheat your oven to 350°F (175°C). Lightly grease a 9x13-inch baking pan and line it with parchment paper, leaving an overhang for easy removal.
Prepare the Brownie Batter:
  1. In a large mixing bowl, whisk together melted butter, granulated sugar, and brown sugar until smooth.
  2. Add the eggs and vanilla extract, whisking until the mixture is light and fluffy.
  3. Sift in the flour, cocoa powder, and salt. Gently fold until just combined.
Assemble the Layers:
  1. Pour half of the brownie batter into the prepared pan, spreading it evenly.
  2. Dollop spoonfuls of peanut butter and marshmallow fluff over the brownie layer. Use a knife or skewer to swirl the toppings lightly.
  3. Pour the remaining brownie batter on top, spreading it to cover the peanut butter and marshmallow swirls.
Bake the Brownies:
  1. Place the pan in the preheated oven and bake for 35–40 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
  2. Allow the brownies to cool completely in the pan on a wire rack (about 45 minutes).
Slice and Serve:
  1. Once cooled, lift the brownie slab out of the pan using the parchment overhang.
  2. Cut into squares with a sharp knife, wiping the blade clean between cuts for neat edges.
  3. Serve and enjoy!

Notes

    • Storage Tips: Store in an airtight container at room temperature for up to 3 days or in the refrigerator for up to 1 week.
    • Freezing Instructions: Wrap individual brownies tightly in plastic wrap and freeze for up to 3 months. Thaw at room temperature before serving.
    • Texture Tips: For a chewier texture, slightly underbake the brownies, ensuring they remain moist in the center.
    • Optional Add-Ins: Sprinkle chopped peanuts or chocolate chips on top before baking for added crunch.
 

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