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Fluffernutter Bars
5 from 1 vote

Fluffernutter Bars

Super soft peanut butter bar cookies with swirls of marshmallow, these Fluffernutter Bars are a peanut butter lover's dream. 

Course Dessert
Cuisine American
Prep Time 10 minutes
Cook Time 25 minutes
Total Time 35 minutes
Servings 16
Author Liz


  • cooking spray
  • 6 Tbs. unsalted butter melted cooled
  • 2 large eggs
  • c. creamy peanut butter not natural peanut butter
  • 1 c. firmly packed light sugar
  • ½ c. granulated sugar
  • c. all-purpose flour
  • ½ c. peanut butter chips optional
  • 6 Tbs. marshmallow fluff
  • mini-marshmallows for topping
  • peanut butter chips for topping


  1. Preheat the oven to 350ºF. Line an 8″ x 8″ baking pan with parchment paper. Spray with cooking spray and set aside.

  2. In a medium size bowl, whisk together the cooled butter, eggs, peanut butter, and both sugars until smooth. Switch to a good silicon spatula or sturdy spoon and mix in flour until just combined. Fold in 1/2 c. peanut butter chips, if using.

  3. Spoon in the marshmallow creme and use a spatula or butter knife to “cut” the marshmallow fluff into the batter. Don't overmix! You want to see some streaks!

  4. Pour the batter into the prepared pan and spread out with clean hands. Add peanut butter chips and torn mini-marshmallows to the top, if desired..

  5. Bake in preheated oven for 25-28 minutes or until a toothpick inserted in the middle of the pan comes out mostly clean. Remove from oven and allow to cool completely on a wire rack before cutting.

Recipe Notes

Fluffernutter Bars will keep for up to 4 days at room temperature (if you can get them to last that long!) or can be frozen for up to 3 months. Defrost in fridge overnight before serving.