Go Back
A three-layer sprinkle cake with vanilla buttercream and rainbow buttercream piped border
Print Recipe
5 from 4 votes

Rainbow Sprinkle Cake

Make your own homemade Funfetti cake with this Rainbow Sprinkle Cake Recipe!
Prep Time30 minutes
Cook Time30 minutes
Total Time1 hour 30 minutes
Course: Dessert
Cuisine: American
Keyword: confetti cake, funfetti cake, rainbow sprinkle cake
Servings: 10

Ingredients

For the Sprinkle Cake

  • 1 cup + 3 tablespoon (150g) all-purpose flour
  • 1 cup + 3 tablespoon (150g) cake flour
  • 2 ¼ teas baking powder
  • ¾ tea salt
  • ¾ cup unsalted butter, softened
  • 1 ½ cup granulated sugar
  • 2 tea vanilla bean paste or extract
  • 3 large eggs
  • ¾ cup (190ml) whole milk
  • cup (78ml) sour cream
  • 1 cup rainbow sprinkles

For the Vanilla Buttercream

  • 1 ½ cups (340g) unsalted butter, softened
  • 4 to 5 cups confectioners' sugar
  • 3 to 5 tablespoon heavy cream
  • 1 teas vanilla bean paste or extract
  • ½ cup rainbow sprinkles

Instructions

To Make the Sprinkle Cake

  • Preheat the oven to 350°F (175°C). Grease and flour three 6-inch cake pans.
  • Sift together the flours, baking powder, and salt. Set aside.
  • In the bowl of a stand mixer fitted with the paddle attachment, beat the butter on medium speed until smooth. Add the sugar and mix medium until light and fluffy, 3 to 5 minutes. Stop the mixer and scrape down the bowl.
  • Turn the mixer to medium-low and add the vanilla. Add the eggs, one at a time, mixing until each is incorporated before adding in the next. Mix until combined. Stop the mixer and scrape down the bowl.
  • Stir the milk and sour cream together. Turn the mixer to low and add the flour mixture in three batches, alternating with the milk mixture, beginning and ending with the flour mixture. Just as the last streaks of flour are combined, stop the mixer and fold in the sprinkles.
  • Evenly divide the batter among the prepares pans. Bake for 26 to 30 minutes, or until a toothpick inserted into the center of the cakes come out clean or with moist crumbs attached. Let the cakes cool on a wire rack for 10 minutes before removing them from their pans. Allow to continue to cool completely frosting the cakes.

To Make the Vanilla Buttercream

  • Using a stand (or hand) mixer fitted with the paddle attachment, beat butter on medium-low speed until smooth and creamy, 1 minute.
  • With the mixer on low speed, gradually add all but 1 cup confectioners’ sugar, 3 tablespoons of cream, and vanilla - scraping the bowl occasionally. Mix until blended.
  • Beat at medium-high speed 3 to 5 minutes, until buttercream is light, airy, and nearly white. If needed, add the additional sugar or cream until desired consistency is achieved. The buttercream should spread smoothly without tearing the crumb of the cake but thick enough that it holds shape when piped and spread between the layers.

To Assemble

  • Place one layer of cake on a cake board or serving dish. Spread on about ¾ cup of the Whipped Vanilla Buttercream with an offset spatula until smooth. Top with the next layer of cake and repeat. Place the last layer on top of the cake. Crumb coat the cake with a thin layer of buttercream then refrigerate the cake for 15 minutes.
  • Reserve about 1 to 1 ½ cups buttercream and set aside. Once chilled, smoothly frost the cake with the remaining buttercream. Using a spoon, scoop and add the sprinkles around the bottom of the cake. Use the back of the spoon or a small offset spatula to gently press them into the buttercream. Use a clean finger tip to fill in any holes or to add sporadic sprinkles on the sides.

Notes

Serve the cake at room temperature. Store leftovers in the refrigerator, in a cake box or covered with plastic wrap, for up to 3 days.