Chewy Fluffernutter Peanut Bars

These Fluffernutter Bars bring together the creamy peanut butter richness and the sweet, airy marshmallow fluff in a chewy, satisfying dessert. They make a perfect treat for a weekend bake or a cozy afternoon snack that reminds me of childhood comfort foods.

I first made this after craving a nostalgic peanut butter marshmallow combo and was delighted at how easily it came together. It quickly became a favorite for sharing with friends.

Ingredients

• All-purpose flour: ensures a sturdy base for the bars and easy texture. Choose a fresh, finely milled flour for best results.
• Baking powder: helps the bars rise just enough without becoming cakey, creating a balanced chewiness
• Salt: enhances the flavors, especially important with sweet and nutty ingredients. I always opt for fine sea salt for even distribution
• Unsalted butter: adds richness and tenderness. Make sure to soften to room temperature for smooth mixing
• Brown sugar: lends a subtle molasses flavor that pairs beautifully with peanut butter
• White sugar: adds just the right amount of sweetness and helps with the chewiness
• Smooth peanut butter: offers a creamy, even texture. Look for natural varieties without added sugars or oils for the cleanest flavor
• Large eggs and egg yolk: contribute to structure and moistness in the dough
• Marshmallow fluff: is the signature sweet topping that makes these bars special. Pick a fresh jar with a fluffy, light texture

Instructions

Preheat Oven:

Set your oven to 350 degrees Fahrenheit and arrange the rack in the middle of the oven. This ensures even baking and prevents the bottoms from burning.

Prepare Pan:

Line a 9 by 13 inch baking pan with parchment paper leaving an overhang for easy removal later. Alternatively, use aluminum foil and lightly grease the surface. This prevents sticking and helps clean up.

Mix Dry Ingredients:

In a medium bowl, whisk together the flour baking powder and salt. This distributes the raising agent evenly through the flour which is key for consistent texture.

Cream Sugars and Butter:

In a large bowl beat the softened butter brown sugar and white sugar until soft and fluffy. This step creates air pockets which helps make the bars more tender.

Incorporate Peanut Butter and Eggs:

Beat in the smooth peanut butter until fully combined. Then add the large egg and egg yolk mixing until smooth. This creates a rich and thick dough.

Add Flour Mixture:

Turn your mixer to low speed and gradually mix in the flour mixture in about two portions. This prevents flour clouds and ensures even mixing without overworking the dough.

Set Aside Batter:

Take about one cup of the dough out of the bowl and set it aside. This portion will be used later as a topping.

Form Base Layer:

Press the remaining peanut butter dough evenly into the bottom of your lined pan using your hands or the back of a spatula. Aim for an even thickness to bake uniformly.

Bake Base Layer:

Place the pan in your preheated oven and bake for 25 minutes or until the top feels set and lightly golden. This step bakes the base perfectly before adding the marshmallow.

Add Marshmallow Fluff:

Carefully remove the pan from the oven, keeping the oven on. Spread the entire jar of marshmallow fluff evenly over the warm peanut butter base. The warmth helps spread it smoothly.

Return to Oven:

Return the pan to the oven and bake for a few more minutes to slightly melt the fluff, creating that signature gooey top without too much browning.

Cool and Serve:

Allow the bars to cool completely in the pan. Use the parchment overhang to lift them out gently before slicing into squares for serving.

My favorite part of these bars is definitely the marshmallow fluff layer. It reminds me of those carefree summer afternoons sharing Fluffernutter sandwiches with my siblings. The way the fluff melts slightly over the warm peanut butter base brings back such happy memories.

Storage Tips

Store leftover bars in an airtight container at room temperature for up to three days or refrigerate for up to a week. To keep the texture soft, bring to room temperature before serving. They freeze beautifully wrapped tightly for up to two months.

Ingredient Swaps

You can swap smooth peanut butter for crunchy if you want extra texture. For a fun twist try almond or sunflower seed butter in the same amount. Using coconut oil in place of butter makes it dairy free though you lose some richness.

Serving Ideas

Serve these bars with a cold glass of milk or a scoop of vanilla ice cream to turn them into a dessert. Chop and sprinkle over yogurt or oatmeal for a sweet peanut butter treat.

Cultural Context

The Fluffernutter originated as a sandwich popular in New England combining peanut butter and marshmallow fluff. This dessert version captures that spirit in a handheld bar form bringing nostalgic flavors to a new generation.

These bars bring nostalgic comfort and satisfy with their perfect chewy texture and sweet marshmallow topping.

Frequently Asked Recipe Questions

→ What helps the bars hold together?

The combination of butter, brown and white sugars creamed together, along with eggs, helps create a firm but chewy texture that holds well once baked.

→ How can I make sure the bars don’t stick while baking?

Lining the pan with parchment paper or aluminum foil and lightly greasing it makes removing the bars easier and prevents sticking.

→ Can I substitute crunchy peanut butter instead of smooth?

Yes, crunchy peanut butter will add some texture, but smooth creates a more even batter and a cohesive bar.

→ Is it necessary to bake the bottom layer before adding the marshmallow fluff?

Baking the bottom layer first ensures it sets and holds its shape, preventing the fluff from soaking in and keeping distinct layers.

→ What is the best way to store these bars?

Once cooled, keep the bars in an airtight container at room temperature or refrigerated for longer freshness.