Dessert

Fluffernutter Brownies Recipe

BySimon Carel March 1, 2026March 1, 2026

Introduction

Fluffernutter Brownies combine rich chocolate with creamy peanut butter and marshmallow fluff for a decadent twist on a classic treat. These brownies are fudgy, sweet, and delightfully gooey, perfect for anyone craving a nostalgic, indulgent dessert.

A square piece of layered dessert sits on a white plate held by a woman's hand at the edge. The dessert has three visible layers: a thick, dark brown, moist brownie base at the bottom, a middle layer of a rich, golden peanut butter filling, and a top layer of glossy, cracked dark chocolate with some patches of white marshmallow peeking through. The cracked top shows texture contrast, and the dessert appears soft and rich. The plate rests on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 ⅓ cups (167.3 g) regular unsweetened cocoa powder
1 cup (125 g) all-purpose flour
1 teaspoon baking powder
½ teaspoon kosher salt
1 teaspoon espresso powder
1 cup (2 sticks / 227 g) unsalted butter, room temperature
2 cups (400 g) granulated sugar
1 cup (168 g) semi-sweet chocolate chips
1 tablespoon vanilla extract
4 large eggs, room temperature
¾ cup (193.5 g) creamy peanut butter
1 cup (96 g) marshmallow fluff

Instructions

Step 1: Preheat the oven to 350°F. Line a 9×13-inch ceramic baking dish with parchment paper.
Step 2: In a large bowl, whisk together cocoa powder, flour, baking powder, salt, and espresso powder. Set aside.
Step 3: In a large saucepan over medium heat, melt the butter with the granulated sugar. Once melted, bring to a low boil and cook for 2 more minutes, stirring occasionally, until the mixture reaches 230°F on an instant-read thermometer.
Step 4: Remove the saucepan from heat. Stir in the chocolate chips and vanilla extract until the mixture is melted and combined. Let it cool for about 10 minutes; it may still look a bit grainy.
Step 5: Add the eggs one at a time, stirring constantly to create a smooth mixture.
Step 6: Fold the dry ingredients into the chocolate mixture until just combined. The batter will be thick.
Step 7: Spread half of the batter evenly into the prepared baking dish.
Step 8: Spread the creamy peanut butter over the batter. Then, pipe or spoon the marshmallow fluff evenly on top of the peanut butter layer.
Step 9: Carefully spread the remaining batter over the marshmallow fluff layer.
Step 10: Bake for 28 to 30 minutes. Allow the brownies to cool completely before cutting and serving.

Tips & Variations

For extra texture, sprinkle chopped peanuts or chocolate chips on top before baking.
To make portioning easier, chill the brownies for an hour before slicing.
Use crunchy peanut butter if you prefer a bit of crunch in every bite.
Add a pinch of cinnamon or chili powder for a subtle spicy twist.

Storage

Store the brownies in an airtight container at room temperature for up to 3 days or refrigerate for up to a week. If refrigerated, bring to room temperature before serving for the best texture. You can also freeze brownies for up to 3 months; thaw overnight in the fridge before enjoying.

How to Serve

A stack of three thick, square brownies with a cracked, dark brown crust on top. Each brownie has three visible layers: the top is a rough, cracked dark brown brownie crust, the middle layer shows patches of white fluffy marshmallow and smooth light brown caramel, and the bottom layer is a dense, dark chocolate brownie base. The brownies are piled on a white marbled surface, with bits of marshmallow and brownie crumbs scattered around. In the background, parts of more brownies are visible but out of focus. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use natural peanut butter instead of creamy peanut butter?

Yes, natural peanut butter can be used but may alter the texture slightly, making the peanut butter layer less smooth. Stir well before spreading to ensure even consistency.

Is espresso powder necessary in this recipe?

Espresso powder enhances the chocolate flavor but is optional. If you don’t have it, you can leave it out or replace it with instant coffee powder for a similar effect.