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banana fluffernutter cake slices

Banana Fluffernutter Cake Recipe

Bernice Baran
Banana Fluffernutter Cake is banana cake with marshmallow fluff swirls and a peanut butter Swiss meringue buttercream.
4.75 from 8 votes
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Prep Time 30 minutes
Cook Time 35 minutes
Additional Time 2 hours
Total Time 3 hours 5 minutes
Course Cakes
Cuisine American
Servings 24 slices
Calories 289 kcal

Ingredients
  

Banana Cake

  • 2 1/2 cups (300g) all-purpose flour spooned and leveled
  • 1 Tbsp (10g) baking powder
  • 1/2 tsp salt
  • 1 tsp cinnamon
  • 1 1/2 cups (300g) light brown sugar lightly packed
  • 2 large eggs room temperature
  • 1/2 cup (113g) greek yogurt
  • 1/2 cup (118mL) vegetable oil
  • 1 tsp vanilla extract
  • 3 large (375g or 1 1/2 cups) ripe bananas mashed (add water to make up the difference to 375g)
  • 1/2 cup (60g) marshmallow fluff

Peanut Butter Buttercream

  • 3/4 cup (150g) light brown sugar lightly packed
  • 4 large egg whites room temperature
  • 1 cup (227g) unsalted butter room temperature
  • 2 tsp vanilla bean paste or vanilla extract
  • 1/2 cup (132g) creamy peanut butter
  • 1/2 cup (60g) marshmallow fluff
  • handful of lightly salted peanuts roughly chopped

Instructions
 

Banana Cake

  • Preheat the oven to 350F/177C convection (325F/163C conventional). Grease and line a 9x13x2-inch (33x23x6cm) cake pan with baking spray and parchment paper.
  • In a medium bowl, whisk together the flour, baking powder, salt and cinnamon. Set aside.
    2 1/2 cups (300g) all-purpose flour, 1 Tbsp (10g) baking powder, 1/2 tsp salt, 1 tsp cinnamon
  • In a large bowl, whisk together the brown sugar and eggs until they’re smooth. Add the greek yogurt, oil and vanilla extract, whisking them until they’re completely combined.
    1 1/2 cups (300g) light brown sugar, 2 large eggs, 1/2 cup (113g) greek yogurt, 1/2 cup (118mL) vegetable oil, 1 tsp vanilla extract
  • Add the bananas to the mixture and mix until they’re fully combined and then fold in the dry ingredients just until the last streak of flour is incorporated.
    3 large (375g or 1 1/2 cups) ripe bananas
  • Slightly heat the marshmallow fluff in the microwave so that it’s a more runny consistency.
    1/2 cup (60g) marshmallow fluff
  • Pour the batter into the prepared pan and dollop the marshmallow fluff on top. Use a knife to swirl it back and forth and then bake for 35 minutes.
  • Remove it from the oven and allow it to cool for at least 30 minutes before removing it from the pan to cool completely.

Peanut Butter Buttercream

  • Make one batch of Swiss Meringue Buttercream using just 3/4 cup of brown sugar in place of the 1 cup of granulated sugar.
    3/4 cup (150g) light brown sugar, 4 large egg whites, 1 cup (227g) unsalted butter
  • Once the buttercream is done, add in the vanilla and peanut butter and mix at medium-high speed, just until it’s combined.
    2 tsp vanilla bean paste, 1/2 cup (132g) creamy peanut butter
  • Spread the buttercream onto the cooled cake and then gently heat the marshmallow fluff again until it’s a little more of a runny consistency.
    1/2 cup (60g) marshmallow fluff
  • Dollop it on top of the buttercream and use an offset spatula to smear it around slightly.
  • Top with peanuts and enjoy!
    handful of lightly salted peanuts

Nutrition

Serving: 1gCalories: 289kcalCarbohydrates: 35gProtein: 4gFat: 15gSaturated Fat: 6gPolyunsaturated Fat: 9gCholesterol: 36mgSodium: 161mgFiber: 1gSugar: 21g
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