Fluffernutter Brownies | Easy Peanut Butter & Marshmallow Treat

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Everyday Culinary Delights👩‍🍳

Posted on January 14, 2025

Few desserts manage to capture the essence of nostalgia and indulgence quite like Fluffernutter Brownies. A delightful twist on the beloved fluffernutter sandwich, these brownies bring together three iconic flavors—rich chocolate, creamy peanut butter, and gooey marshmallow—to create a dessert that’s both comforting and irresistibly decadent.

Whether you’re baking for a party, treating yourself after a long day, or simply looking to impress with a unique take on brownies, this recipe is guaranteed to be a showstopper.

What Makes Fluffernutter Brownies So Special?

At their core, Fluffernutter Brownies take a classic fudgy brownie base and elevate it with swirls of peanut butter and marshmallow fluff. The result? A perfect balance of textures and flavors:

The Brownie Base – Dense, fudgy, and intensely chocolatey, providing a rich foundation.
Peanut Butter Swirls – Salty and creamy, cutting through the sweetness and adding depth.
Marshmallow Fluff – Light, gooey, and slightly caramelized when baked, adding a unique contrast to the rich layers.

Each bite delivers a combination of melt-in-your-mouth chocolate, nutty creaminess, and marshmallow sweetness, making this an elevated brownie experience.

Ingredients:

For the Brownie Base:

Unsalted Butter: 1 cup (226g), melted
Granulated Sugar: 1 1/4 cups (250g)
Light Brown Sugar: 3/4 cup (150g), packed
Eggs: 3 large, room temperature
Vanilla Extract: 2 teaspoons
All-Purpose Flour: 3/4 cup (95g)
Unsweetened Cocoa Powder: 1/2 cup (45g)
Kosher Salt: 1/2 teaspoon

For the Fluffernutter Layer:

Creamy Peanut Butter: 1 cup
Marshmallow Fluff or Cream: 1 1/2 cups

Directions:

Preheat the Oven:
- Preheat oven to 350°F (175°C).
- Grease a 9×13-inch baking pan and line with parchment paper, leaving an overhang.
Prepare the Brownie Batter:
- In a large bowl, whisk together melted butter, granulated sugar, and brown sugar until smooth.
- Add eggs and vanilla extract, whisking until light and fluffy.
- Sift in flour, cocoa powder, and salt, then gently fold until combined.
Assemble the Layers:
- Pour half of the brownie batter into the prepared pan, spreading evenly.
- Dollop spoonfuls of peanut butter and marshmallow fluff over the layer.
- Swirl with a knife for a marbled effect.
- Pour the remaining brownie batter on top, spreading evenly.
Bake the Brownies:
- Bake for 35–40 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.
- Let the brownies cool completely in the pan on a wire rack.
Slice and Serve:
- Once cooled, lift brownies out using parchment overhang.
- Slice into squares with a sharp knife, wiping the blade clean between cuts.

Nutritional Information (Per Serving):

Calories: 320
Protein: 5g
Fat: 18g
Carbohydrates: 37g
Fiber: 2g
Sodium: 150mg

Why You’ll Love This Recipe

Fluffernutter Brownies are more than just a dessert—they’re an experience. Here’s why you should make them:

1. They Offer the Best of All Worlds

Can’t decide between a brownie, peanut butter cookie, or a marshmallow treat? This recipe gives you all three in one bite.

2. They Are Visually Stunning

The beautiful swirls of peanut butter and marshmallow fluff create a gorgeous marbled effect, making these brownies just as stunning as they are delicious.

3. They’re a Crowd-Pleaser

These brownies appeal to kids and adults alike, making them perfect for birthday parties, bake sales, or special occasions.

4. They Have the Perfect Texture

Unlike some brownies that can be either too cakey or too dense, this recipe delivers a moist, fudgy texture with a gooey, chewy topping that keeps you coming back for more.

5. They Can Be Customized

Love extra peanut butter? Prefer more chocolate? Want to add a little crunch? This recipe is highly adaptable, allowing you to adjust mix-ins to suit your taste.

Tips for Making the Perfect Fluffernutter Brownies

Baking brownies may seem simple, but a few key techniques will ensure your Fluffernutter Brownies turn out perfectly every time.

1. Use High-Quality Ingredients

Since this recipe relies on simple yet bold flavors, using high-quality cocoa powder, pure vanilla extract, and natural peanut butter can make a world of difference.

2. Melt Butter for a Fudgier Texture

Instead of creaming butter and sugar together, melting the butter first allows for a denser, fudgier consistency.

3. Don’t Overmix the Batter

Overmixing can incorporate too much air, leading to cakier brownies. Gently fold the dry ingredients into the wet ingredients just until combined.

4. Create the Perfect Swirls

When adding peanut butter and marshmallow fluff, dollop spoonfuls over the brownie batter and use a butter knife or toothpick to swirl them together lightly. Overmixing the swirls can cause them to blend too much into the batter, losing that signature marbled look.

5. Let the Brownies Cool Completely

Although it’s tempting to dig in right away, letting the brownies cool allows them to set, making slicing easier and ensuring the layers hold their shape.

Fun Variations to Try

The beauty of Fluffernutter Brownies is their versatility. Try these delicious variations to put your own twist on this classic recipe:

1. Crunchy Fluffernutter Brownies

For added texture, sprinkle chopped peanuts or crushed pretzels on top before baking.

2. Chocolate Lovers’ Fluffernutter Brownies

Mix in dark chocolate chunks or drizzle melted chocolate over the baked brownies for an even richer, more indulgent version.

3. S’mores-Inspired Brownies

Substitute the marshmallow fluff with mini marshmallows and add crushed graham crackers to the batter for a s’mores brownie hybrid.

4. Nut-Free Fluffernutter Brownies

If you have a peanut allergy, swap the peanut butter for almond butter, cashew butter, or sunflower seed butter.

5. Salted Caramel Fluffernutter Brownies

Drizzle salted caramel sauce over the peanut butter and marshmallow swirls before baking for a sweet-salty contrast.

Frequently Asked Questions (FAQs)

1. Can I Use a Boxed Brownie Mix Instead?

Yes! If you’re short on time, a boxed brownie mix can work as a great shortcut. Simply prepare the mix as directed, then follow the same steps for swirling in peanut butter and marshmallow fluff.

2. Can I Make These Gluten-Free?

Absolutely! Just substitute all-purpose flour with a 1:1 gluten-free flour blend, and double-check that all ingredients, including marshmallow fluff and peanut butter, are gluten-free.

3. What’s the Best Way to Cut These Brownies Cleanly?

For neat, professional-looking slices:

Let the brownies cool completely.
Use a sharp knife dipped in warm water and wipe it clean between each cut.

4. Can I Freeze Fluffernutter Brownies?

Yes! Wrap individual brownie squares in plastic wrap, then store them in an airtight container in the freezer for up to 3 months. Thaw at room temperature before serving.

5. How Do I Store These Brownies?

At room temperature: Store in an airtight container for up to 3 days.
In the fridge: Store for up to a week for a chewier texture.

6. Can I Use Crunchy Peanut Butter?

Definitely! Crunchy peanut butter adds an extra nutty bite and slight crunch to the soft texture of the brownies.

Final Thoughts: Why You Need to Try Fluffernutter Brownies

Fluffernutter Brownies are more than just dessert—they’re an experience. The combination of fudgy chocolate, gooey marshmallow, and creamy peanut butter makes each bite feel like pure indulgence.

Whether you’re looking for a crowd-pleasing dessert, a nostalgic throwback to childhood, or just an excuse to enjoy something deliciously over-the-top, these brownies won’t disappoint.

So go ahead—gather your ingredients, preheat your oven, and get ready for the best brownies you’ve ever made. Once you try them, they might just become your new favorite dessert.