Fluffernutter Bars Recipe
Introduction
Fluffernutter Bars combine the classic flavors of peanut butter and marshmallow fluff into a delightful dessert that’s soft, creamy, and irresistibly sweet. These bars are perfect for anyone looking for a nostalgic treat with a modern twist.

Ingredients
- 2 1/2 cups all purpose flour
- 1/2 teaspoon baking soda
- 1 teaspoon salt
- 3/4 cup unsalted butter, at room temperature
- 3/4 cup smooth peanut butter
- 1/2 cup granulated sugar
- 1 cup packed light brown sugar
- 2 large eggs, at room temperature
- 2 teaspoons vanilla extract
- 1 (7 ounce) jar marshmallow fluff
- 1/2 cup smooth peanut butter (for filling)
- 3 tablespoons unsalted butter, at room temperature (for filling)
- 1 1/2 cups sifted powdered sugar
- 3 tablespoons heavy cream
- 1/2 teaspoon vanilla extract (for filling)
Instructions
- Step 1: Preheat the oven to 350°F. Grease and line a 9×9 inch baking pan with parchment paper, leaving an overhang for easy removal.
- Step 2: In a medium bowl, whisk together the flour, baking soda, and salt. Set aside.
- Step 3: In a large bowl, cream together the butter, peanut butter, granulated sugar, and brown sugar until light and fluffy, about 2-3 minutes. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.
- Step 4: Gradually add the flour mixture to the wet ingredients, mixing until just combined.
- Step 5: Press the dough evenly into the prepared pan. Bake for 25-30 minutes, or until lightly browned and a toothpick inserted into the center comes out clean. Remove from the oven and let cool slightly.
- Step 6: While the bars are cooling, prepare the peanut butter filling. In a medium bowl, beat together peanut butter and butter until smooth. Add powdered sugar, vanilla extract, and 2 tablespoons of heavy cream. Beat until smooth and creamy, adding an additional tablespoon of heavy cream if needed to achieve a spreadable consistency.
- Step 7: Using the back of a spoon or an offset spatula, spread the peanut butter filling over the warm bars in the pan.
- Step 8: Warm the marshmallow fluff in the microwave for a few seconds to make it easier to spread. Spread the fluff evenly over the peanut butter filling.
- Step 9: Allow the bars to cool completely in the pan before slicing into squares. Serve at room temperature.
Tips & Variations
- For a crunchier texture, sprinkle chopped peanuts over the marshmallow layer before it sets.
- Use creamy or chunky peanut butter depending on your preferred texture.
- To make these bars nut-free, substitute the peanut butter with sunflower seed butter.
- Chilling the bars for an hour before slicing helps achieve cleaner cuts.
Storage
Store the Fluffernutter Bars in an airtight container at room temperature for up to 3 days. For longer storage, keep them refrigerated for up to a week. Bring to room temperature before serving for the best flavor and texture. These bars can also be frozen for up to 2 months; thaw overnight in the fridge and serve the next day.
How to Serve

Serve this delicious recipe with your favorite sides.
FAQs
Can I use natural peanut butter for this recipe?
Yes, natural peanut butter works well, but it may affect the texture of the batter and filling because it tends to be thinner and oilier than processed peanut butter. You might need to adjust the amount of powdered sugar or cream in the filling to maintain the right consistency.
How can I tell when the bars are done baking?
The bars are done when the edges are lightly browned and a toothpick inserted into the center comes out clean or with just a few moist crumbs. Avoid overbaking to keep them soft and tender.
PrintFluffernutter Bars Recipe
Fluffernutter Bars combine the classic flavors of peanut butter and marshmallow fluff in a chewy, buttery cookie bar. These delightful treats feature a soft peanut butter base topped with a creamy peanut butter frosting and a layer of sweet marshmallow fluff, making for a nostalgic and irresistible dessert perfect for any occasion.
- Prep Time: 20 minutes
- Cook Time: 30 minutes
- Total Time: 50 minutes
- Yield: 16 bars 1x
- Category: Dessert
- Method: Baking
- Cuisine: American
Ingredients
For the Bar Base
- 2 1/2 cups all purpose flour
- 1/2 teaspoon baking soda
- 1 teaspoon salt
- 3/4 cup unsalted butter, at room temperature
- 3/4 cup smooth peanut butter
- 1/2 cup granulated sugar
- 1 cup packed light brown sugar
- 2 large eggs, at room temperature
- 2 teaspoons vanilla extract
For the Peanut Butter Filling
- 1/2 cup smooth peanut butter
- 3 tablespoons unsalted butter, at room temperature
- 1 1/2 cups sifted powdered sugar
- 3 tablespoons heavy cream, divided
- 1/2 teaspoon vanilla extract
For the Topping
- 1 (7 ounce) jar marshmallow fluff
Instructions
- Preheat Oven and Prepare Pan: Preheat your oven to 350°F (175°C). Grease a 9×9 inch baking pan and line it with parchment paper, leaving an overhang on the sides to make it easier to remove the bars later.
- Mix Dry Ingredients: In a medium bowl, whisk together the all purpose flour, baking soda, and salt. Set this mixture aside for later incorporation.
- Cream Wet Ingredients: In a large bowl, use an electric mixer to cream together the room temperature unsalted butter, smooth peanut butter, granulated sugar, and light brown sugar until the mixture is light and fluffy, about 2 to 3 minutes. This aerates the mixture and ensures a tender texture.
- Add Eggs and Vanilla: Add the eggs one at a time, beating well after each addition to ensure they are fully incorporated. Stir in the vanilla extract for flavor.
- Combine the Batter: Gradually add the dry flour mixture to the wet ingredients, mixing just until combined. Avoid overmixing to keep the bars tender.
- Bake the Bars: Press the dough evenly into the prepared baking pan. Place in the oven and bake for 25 to 30 minutes, or until the edges are lightly browned and a toothpick inserted into the center comes out clean. Remove from the oven and allow to cool slightly.
- Prepare Peanut Butter Filling: While the bars cool, prepare the filling. In a medium bowl, beat together the remaining peanut butter and unsalted butter until smooth. Add sifted powdered sugar, vanilla extract, and 2 tablespoons of heavy cream. Beat until smooth and creamy. If the filling is too thick, add the remaining tablespoon of heavy cream to achieve a spreadable consistency.
- Spread Peanut Butter Filling: Using a spatula or the back of a spoon, evenly spread the peanut butter filling over the warm bars in the pan to create a smooth layer.
- Top with Marshmallow Fluff: Warm the marshmallow fluff in the microwave for about 10-15 seconds to soften it, making it easier to spread. Carefully spread the marshmallow fluff over the peanut butter layer, covering it completely.
- Cool and Serve: Allow the assembled bars to cool completely in the pan at room temperature. Once cooled, use the parchment paper overhang to lift the bars out of the pan and slice into squares. Serve at room temperature for the best texture and flavor.
Notes
- You can substitute creamy peanut butter with natural peanut butter, but ensure it is well stirred to combine the oils.
- For easier spreading, make sure the marshmallow fluff is slightly warmed before applying.
- Store the bars in an airtight container at room temperature for up to 3 days or refrigerate for up to a week.
- These bars can be cut smaller for bite-sized treats perfect for parties or lunchboxes.
- Use parchment paper to easily lift the bars out without damaging the edges.
Keywords: Fluffernutter bars, peanut butter bars, marshmallow fluff dessert, baked peanut butter bars, easy dessert recipe

