Marshmallow Peanut Butter Brownies Recipe

Introduction

These Marshmallow Peanut Butter Brownies combine rich, fudgy chocolate with creamy peanut butter swirls and fluffy marshmallow topping. Perfect for anyone who loves a decadent treat with a fun twist.

Ingredients

• Peanut Butter Filling:
• 1/2 cup creamy peanut butter
• 1/4 cup powdered sugar
• 2 tbsp unsalted butter, room temperature
• Pinch of salt
• Brownies:
• 1 cup + 2 tbsp all-purpose flour
• 3/4 tsp salt
• 1/2 tsp baking powder
• 4 large eggs, room temperature
• 1 1/2 cups granulated sugar
• 1/2 cup packed brown sugar
• 1/2 cup canola oil
• 2 tsp pure vanilla extract
• 8 tbsp unsalted butter
• 8 oz bittersweet chocolate, chopped
• 1/4 cup Dutch process cocoa powder
• 1/2 cup store-bought marshmallow fluff

Instructions

1. Step 1: Prepare the peanut butter filling by mixing peanut butter, powdered sugar, unsalted butter, and a pinch of salt in a medium bowl until smooth. Set aside.
2. Step 2: Preheat the oven to 350ºF (180ºC). Grease a 9×13 inch baking pan and line with a parchment sling for easy removal.
3. Step 3: In a small bowl, whisk together the flour, salt, and baking powder.
4. Step 4: In another bowl, whisk the eggs with both sugars, canola oil, and vanilla extract until combined.
5. Step 5: Melt the butter and chopped chocolate together in a small saucepan over low heat, stirring frequently. Once smooth, remove from heat and whisk in the cocoa powder until fully blended.
6. Step 6: Add the chocolate mixture to the egg mixture and whisk until smooth. Stir in the flour mixture until just combined.
7. Step 7: Pour the brownie batter into the prepared pan. Alternately dollop the peanut butter filling and marshmallow fluff on top.
8. Step 8: Use the tip of a butter knife to swirl the fillings gently through the batter to create a marbled effect.
9. Step 9: Bake for 26 to 32 minutes. The edges should be set with a glossy, crackled top and a toothpick inserted in the center should come out with moist crumbs but no wet batter.
10. Step 10: Transfer the pan to a wire rack and let the brownies cool completely. Use the parchment sling to lift them out, cut into bars, and serve.

Tips & Variations

• Use a parchment sling for easy removal and cleaner cuts.
• Warm the marshmallow fluff briefly in the microwave (about 15 seconds) to make dolloping easier.
• For melting chocolate and butter, you can alternatively microwave in 45–60 second bursts at medium power, stirring in between to prevent scorching.
• Swap canola oil for melted coconut oil for a subtle flavor twist.

Storage

Store the brownies in an airtight container at room temperature for up to 2 days. For longer storage, refrigerate for up to a week and allow to come to room temperature before serving. Reheat briefly in the microwave if you prefer them warm.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use crunchy peanut butter instead of creamy?

Yes, but the filling will have a slightly different texture due to the peanut pieces. The brownies will still be delicious.

Is there a substitute for marshmallow fluff?

You can use homemade marshmallow cream or a few dollops of marshmallow creme as a replacement. Avoid mini marshmallows as they won’t swirl as nicely on top.

Marshmallow Peanut Butter Brownies Recipe

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These decadent Marshmallow Peanut Butter Brownies feature a rich, fudgy chocolate base swirled with creamy peanut butter filling and fluffy marshmallow cream. Baked to perfection with a glossy, crackling top and a soft, moist crumb, these brownies combine luscious textures and flavors that are perfect for any chocolate lover looking for a delightful twist.

• Author: Elena
• Prep Time: 20 minutes
• Cook Time: 30 minutes
• Total Time: 50 minutes
• Yield: 12–16 brownies 1x
• Category: Dessert
• Method: Baking
• Cuisine: American

Ingredients

Scale 1x2x3x

Peanut Butter Filling

• 1/2 cup Creamy Peanut Butter
• 1/4 cup Powdered Sugar
• 2 tbsp Unsalted Butter, room temperature
• Pinch of Salt

Brownies

• 1 cup + 2 tbsp All-Purpose Flour
• 3/4 tsp Salt
• 1/2 tsp Baking Powder
• 4 Large Eggs, room temperature
• 1 1/2 cups Granulated Sugar
• 1/2 cup Brown Sugar, packed
• 1/2 cup Canola Oil
• 2 tsp Pure Vanilla Extract
• 8 tbsp Unsalted Butter
• 8 oz Bittersweet Chocolate, chopped
• 1/4 cup Dutch Process Cocoa Powder
• 1/2 cup Store-Bought Marshmallow Fluff

Instructions

1. Make the Peanut Butter Filling: In a medium bowl, combine the creamy peanut butter, powdered sugar, room temperature unsalted butter, and a pinch of salt. Mix thoroughly until the mixture is completely smooth and well combined. Set aside for later use.
2. Prepare Oven and Pan: Adjust an oven rack to the middle and preheat your oven to 350ºF (180ºC). Grease a 9×13 inch (23×33 cm) baking pan and line it with a parchment sling to facilitate easy removal of brownies after baking.
3. Mix Dry Ingredients: In a small bowl, whisk together the all-purpose flour, salt, and baking powder until evenly combined.
4. Combine Wet Ingredients: In another bowl, whisk together the eggs, granulated sugar, brown sugar, canola oil, and vanilla extract until the mixture is smooth and homogenous.
5. Melt Chocolate and Butter: Place the unsalted butter and chopped bittersweet chocolate in a small heavy-bottom saucepan over low heat. Stir frequently to prevent scorching until melted and smooth. Remove from heat and whisk in the Dutch process cocoa powder until fully incorporated.
6. Combine Chocolate with Egg Mixture: Pour the melted chocolate mixture into the sugar-egg mixture and whisk to combine smoothly. Then add the flour mixture and gently fold in until just combined without overmixing.
7. Assemble the Brownies: Pour the brownie batter into the prepared pan, spreading evenly. Dollop the peanut butter filling and spoon the store-bought marshmallow fluff over the top alternately. Using the tip of a butter knife, create swirls by dragging it through the batter to combine the toppings visually without fully mixing.
8. Bake the Brownies: Bake in the preheated oven for 26 to 32 minutes until the edges are set, the top has a glossy crackled appearance, and a wooden skewer inserted in the center comes out with moist crumbs clinging but no wet batter.
9. Cool and Serve: Remove the pan from the oven and place it on a wire rack to cool completely. Once cooled, use the parchment sling to lift the brownie slab out of the pan. Cut into bars and serve. Store any leftovers in an airtight container at room temperature for up to 2 days.

Notes

• This recipe is adapted from the 100 Cookies cookbook by Sarah Kieffer and Chronicle Books LLC, with permission.
• Using a parchment sling is very helpful for removing the brownies cleanly from the pan and makes cutting easier.
• Heating the marshmallow fluff in the microwave for about 15 seconds softens it for easier dolloping onto the brownies.
• Alternatively, to melt the chocolate and butter, you can microwave at medium power for 45–60 seconds, stir, and repeat until fully melted and smooth.

Keywords: Marshmallow peanut butter brownies, chocolate brownies, peanut butter dessert, fudgy brownies, marshmallow brownies