Harry Potter butterbeer cake with marshmallow frosting

  • Author: Tiffany Dahle
  • Prep Time: 30 min
  • Cook Time: 40 min
  • Total Time: 1 hour 10 minutes
  • Yield: 12
  • Category: Cakes
  • Method: Baking


This sweet and simple Harry Potter cake tastes just like a butterbeer with marshmallows. Your little wizard-in-training will swoon over this magical cake.


For the Cake:

  • 2 1/4 cups flour
  • 2 1/4 tsp baking powder
  • 1 (3.5 oz) butterscotch instant pudding mix
  • 1/2 tsp salt
  • 3/4 cup butter, softened
  • 1 cup granulated sugar
  • 3 eggs
  • 1 1/4 cups cream soda, clear or brown — it will affect the color of your cake
  • 1 tsp vanilla extract

For the marshmallow frosting:

  • 1 1/2 cups butter, softened
  • 4 cups powdered sugar
  • 1 (14 oz) canister of marshmallow fluff
  • 1 tsp vanilla extract — use clear vanilla if you want bright-white frosting

For serving:

  • butterscotch sauce (optional)
  • ice cream (optional)


Preheat the oven to 350 degrees. Rub softened butter all around the inside of 3 8-inch cake pans. Line the bottoms of the pans with parchment paper and then dust them with flour. Set aside.

In a medium bowl, add the flour, baking powder, pudding mix, and salt. Whisk them together and set aside.

Add the butter and sugar to your mixing bowl and beat them together with an electric mixer until they are light and fluffy. Scrape the bowl. 

Add one egg at a time and gently beat it with the mixer to incorporate before adding the next egg. Scrape the bowl and add the vanilla. Mix to combine.

Add half the flour mixture to the mixing bowl and stir to combine. Pour the cream soda in and stir to combine. Then add the remaining flour and stir to combine. Scrape the bowl and check for any dry pockets of flour.

Pour the cake batter evenly among the cake pans. Bake for 30 – 40 minutes or until a toothpick inserted in the center comes out clean. Allow the cakes to cool completely before frosting.

Assemble the frosting:

Add the butter to your mixing bowl. Beat it with an electric mixer until it is smooth and creamy. Scrape the bowl. Add the powdered sugar one cup at a time and beat it until completely combined before adding the next cup. 

Beat the butter and sugar together for 3 minutes until light and fluffy. Add the marshmallow fluff and vanilla and continue to beat for an additional 2-3 minutes.

Assemble the cake:

Use the frosting to ice between the layers of the cake and all over the tops and sides of the finished cake. Chill until serving time. 

Heat the butterscotch sauce in the microwave for 10 – 15 seconds or until it is loose and drizzly. Serve alongside the cake in a small cream pitcher for drizzling on top of each slice.

Keywords: Harry Potter, birthday cake, butterbeer, marshmallow frosting, butterscotch