These Fluffernutter Bars combine salted peanut butter cookie layers and marshmallow fluff baked together into a delightfully gooey treat that is sure to please!
Peanut butter cookies: Good. Marshmallow fluff: Good. Baked together into one delightful marshmallow peanut butter bar: DELICIOUS! These bars are inspired by the Fluffernutter sandwich which is a peanut butter and marshmallow fluff sandwich.
If you love peanut butter, like in my Chocolate Chip Peanut Butter Cookies or Peanut Butter Granola, you are going to love these bars! Be sure to also try my Chocolate Peanut Butter Brownies.
I like peanut butter but the real attraction for me in these bars is the marshmallow fluff!! I adore that stuff. I cannot resist eating it by the spoonful whenever I have some in the pantry. Or on salted potato chips... don't ask me how I know that lol. Be sure to try my No-Bake Mini S'mores Cheesecakes if you love marshmallow fluff too!
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⭐️ Why You Need to Make This Recipe
- Flavor - Sweet vanilla marshmallow and salty peanut butter come together in these tasty bars that are sure to thrill young and old alike!
- Texture - The soft and tender peanut butter cookie dough layers bake together with the fluffy and gooey marshmallow into an irresistible textured dessert.
- Method - These peanut butter marshmallow bars are super easy to make in no time!
🧈 Ingredients
Here are the ingredients needed to make these Fluffernutter Marshmallow Peanut Butter Bars.
Ingredient Notes
- Butter - As in most of my cookie recipes, I use salted butter for these bars but you could use unsalted butter instead with an additional ¼ teaspoon of salt added to the recipe.
- Peanut Butter - You can use smooth or crunchy, whichever you prefer. I would recommend avoiding natural peanut butter for this recipe, however, as the texture is much different than a Kraft, Jif, or Skippy-type creamy peanut butter.
- Marshmallow Fluff - You must only use marshmallow fluff for this recipe. Regular marshmallows will melt and turn clear while the bars bake and leave you with a sticky and hard layer of melted marshmallows - marshmallow fluff keeps its form even after baking. Either Jet Puffed or Fluff brand marshmallow fluff/creme would work great here.
See the recipe card for the full list of ingredients with measurements.
📃 Instructions
Step 1: Cream together the softened butter, peanut butter, sugar, and brown sugar until smooth.
Step 2: Add the egg and vanilla and continue mixing at high speed until fluffy.
Step 3: In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Add to the wet ingredients and mix at low speed just until incorporated.
Step 4: Spread about ⅔ of the cookie dough into the bottom of a baking pan that has been lined with parchment paper.
Step 5: Spread the marshmallow fluff in an even layer over the layer of cookie dough using a greased spatula.
Step 6: Drop the remaining cookie dough over the marshmallow fluff layer and very gently spread it out as best as you can.
Bake in a preheated oven for 25-30 minutes or until puffed up and golden around the edges.
💡 Top Tip
You must only use marshmallow fluff for this recipe. Regular marshmallows will melt and turn clear while the bars bake and leave you with a sticky and hard layer of melted marshmallow - marshmallow fluff keeps its form even after baking.
❓ Recipe FAQs
No. You must only use marshmallow fluff for this recipe. Regular marshmallows will melt and turn clear while the bars bake and leave you with a sticky and hard layer of melted marshmallow - marshmallow fluff keeps its form even after baking.
Yes! Use creamy or crunchy, whichever type you prefer. I have not tested this recipe with a natural-style peanut butter though so I do not know how that would turn out and therefore recommend a Kraft or Jif-style peanut butter.
Store leftover fully cooled bars covered tightly or in an airtight container at room temperature for up to 4 days.
🥜 More Peanut Butter Recipes
Looking for other recipes like this? Try these:
If you tried these Fluffernutter Bars or any other recipe on my website, please leave a ⭐️ star rating and write a little note telling me how it went in the comments below. Thank you!!
📖 Recipe
Fluffernutter Bars (Marshmallow Peanut Butter Bars)
Equipment
- 9x9-inch baking pan
- parchment paper
- mixing bowl
- electric handheld mixer
- measuring cups & spoons
Ingredients
- ½ cup salted butter *(softened)
- ½ cup creamy peanut butter
- ¾ cup packed brown sugar
- ¼ cup granulated white sugar
- 1 egg
- 1 teaspoon vanilla extract
- 1 cup all-purpose flour
- ½ teaspoon baking soda
- ¼ teaspoon baking powder
- ¼ teaspoon salt
- 1 cup marshmallow fluff *
Instructions
- Preheat the oven to 350℉. Line a 9x9-inch baking pan with parchment paper.
- In a mixing bowl using an electric mixer, cream together the softened butter, brown sugar, and white sugar for 30 seconds. Add the egg and vanilla and continue creaming at high speed until fluffy.½ cup salted butter, ¾ cup packed brown sugar, ¼ cup granulated white sugar, 1 egg, 1 teaspoon vanilla extract, ½ cup creamy peanut butter
- In a separate bowl, whisk together the flour, baking soda, baking powder, and salt. Add to the wet ingredients and continue mixing at low speed just until incorporated. Spread about ⅔ of the mixture into the bottom of the prepared baking pan, smoothing it into an even layer.1 cup all-purpose flour, ½ teaspoon baking soda, ¼ teaspoon baking powder, ¼ teaspoon salt
- Add the marshmallow fluff on top of the batter and spread all around with a greased spatula as best as you can. Lastly, top with dollops of the remaining batter all over on top of the marshmallow fluff. Spread the batter out as best as you can.1 cup marshmallow fluff
- Bake the bars in the preheated oven for 25-30 minutes or until lightly golden around the edges and puff up in the center. Let cool slightly before lifting the bars out of the pan using the parchment paper as a handle. Slice and serve. Enjoy!
Notes
- Or use unsalted butter with an additional ¼ teaspoon of salt added to the recipe.
- You must only use marshmallow fluff for this recipe. Regular marshmallows will melt while the bars bake and leave you with a sticky and hard layer of melted marshmallow - marshmallow fluff keeps its form even after baking.
Mandalynn
I remember back when Leah first told me about your site. Can't believe it's been eight years. Good on you for persevering. And your recipes always look scrumptious.
Camille Nicolini
Hi !
Seems like there is no quantity
Of peanut butter listed in ingredients
Can you tell me how much ? Thanks
Naomi Andres
Hi Camille,
I am very sorry about that, thank you for bringing it to my attention. I have updated the recipe with the measurement. It is 1/2 cup of peanut butter.
Thanks,
Naomi