Rainbow Birthday Cake

Total Time

Prep: 1 hour Bake: 30 min. + cooling

Makes

16 servings

Updated: Aug. 26, 2023
How fun is this rainbow birthday cake? It will add a festive touch to any celebration. Be sure to use gel food coloring for the most vibrant look. —Taste of Home Test Kitchen
Rainbow Birthday Cake Recipe photo by Taste of Home

Ingredients

  • 1 cup butter, softened
  • 2-1/2 cups sugar
  • 4 large eggs, room temperature
  • 4 cups all-purpose flour
  • 3 teaspoons baking powder
  • 1 teaspoon salt
  • 1/2 teaspoon baking soda
  • 1-1/2 cups sour cream
  • 6 different colors gel food coloring
  • FROSTING:
  • 2 cups butter, softened
  • 6 cups confectioners' sugar, sifted
  • 2 teaspoons vanilla extract
  • 1/4 to 1/3 cup heavy whipping cream
  • Sprinkles

Directions

  1. Preheat oven to 350°. Line bottoms of 3 greased and floured 8-in. round baking pans with parchment; grease paper. In a large bowl, cream butter and sugar until light and fluffy, 5-7 minutes. Add eggs, 1 at a time, beating well after each addition. Combine flour, baking powder, salt and baking soda; add to the creamed mixture alternately with sour cream, beating well after each addition. Divide batter into equal portions, with 1-1/4 cups in 6 separate bowls. Tint each portion a different color with food coloring. Cover and refrigerate 3 portions.
  2. Transfer 3 remaining portions to prepared pans. Bake until edges begin to just brown, 13-15 minutes. Cool for 10 minutes before removing from pans to wire racks to cool completely. Cool, wash and dry pans. Repeat with remaining batter.
  3. For frosting, in a large bowl, beat butter until fluffy. Gradually beat in confectioners' sugar. Beat in vanilla and enough cream to reach desired consistency. Spread frosting between layers and over top and side of cake. Decorate with sprinkles.
Rainbow Birthday Cake Tips

How can you make sure each layer of cake is evenly thick?

To make sure your cake layers are uniformly thick, give your cake tins a good tap on the counter before putting them in the oven. Doing so will help release extra air bubbles trapped beneath the surface, and level everything out so the batter is evenly dispersed. Find more tips for how to level a cake to make sure your layered rainbow cake turns out perfectly.

How can you make a rainbow birthday cake your own?

There are many ways you can have fun customizing a rainbow birthday cake. Try decorating the cake with edible glitter, sprinkles or other unique cake decorations, like freeze-dried marshmallows or fondant. Instead of doing one color per cake layer, you can also mix several colors into each pan and mix it with a toothpick in order to get a swirling pattern. Pull inspiration from other rainbow desserts.

How should you store rainbow birthday cake?

Store leftover rainbow birthday cake in the refrigerator under a cake dome or in a cake keeper. If the cake is sliced, press plastic wrap against the exposed sponge in order to keep it from drying out. Cake should last about 3 to 4 days when stored this way. Check out our guide to how to store cake if you want more tips, including how to freeze cake and how to store leftover frosting.

—Sammi DiVito, Taste of Home Assistant Editor

Nutrition Facts

1 piece: 793 calories, 42g fat (26g saturated fat), 158mg cholesterol, 579mg sodium, 101g carbohydrate (77g sugars, 1g fiber), 6g protein.