Rainbow Cake

rainbow cake

 Leah Maroney

  • Total: 80 mins
  • Prep: 45 mins
  • Cook: 35 mins
  • Yield: 1 cake (serves 12)

With each layer dyed a different color, this showstopping rainbow cake may seem too hard to create a home. Not so! The gorgeous dessert requires little complicated cake decorating skills. All you need to do is bake, stack, and frost.

The opportunities to use this cake are endless. Whip one up for St. Patrick's Day, kids birthday parties, or a colorful baby shower. It's sure to impress and entertain all of your guests—big and small!

Ingredients

  • 1 1/2 cup unsalted butter (softened)
  • 3 cups sugar
  • 3 teaspoons vanilla
  • 4 1/2 cups cake flour
  • 2 tablespoons baking powder
  • 2 teaspoons salt
  • 2 cups milk
  • 10 egg whites
  • 4 to 5 pounds vanilla frosting

Steps to Make It

  1. Gather the ingredients.

    rainbow cake
    Leah Maroney 
  2. Beat the sugar and butter until creamy and whipped, about 10 minutes.

    rainbow cake
     Leah Maroney
  3. Whisk together the flour, baking powder, and salt in a bowl until completely combined.

    rainbow cake
    Leah Maroney 
  4. Scrape down the sides of the bowl. Add the flour mixture to the butter and sugar mixture and beat until roughly combined.

    rainbow cake
    Leah Maroney 
  5. Scrape down the sides of the bowl. Blend in the milk and vanilla extract, beat for one minute or until combined and smooth.

    rainbow cake
     Leah Maroney
  6. Beat the egg whites until they form stiff peaks.

    rainbow cake
    Leah Maroney 
  7. Fold the egg whites into the cake batter until combined. Do this gently so as to not deflate all of the egg whites, but also make sure it's totally combined. Scrape down the sides of the bowl.

    rainbow cake
     Leah Maroney
  8. Split the batter evenly into 8 different small bowls. Whisk the food coloring into each bowl. You will need: red, pink, orange, yellow, green, blue, light blue, and purple. You can skip the pink or light blue if you want to do fewer layers; just split the batter into 6 or 7 bowls. You will need more food coloring than you think to get the right hue. The cake will lighten as it bakes so the color needs to be very saturated to stay vibrant. Add a few drops at a time until you reach your desired tone.

    rainbow cake
    Leah Maroney 
  9. Prepare four round baking pans. You can use 8- or 9-inch cake pans. Grease the entire pan, then dust with flour, shaking off the excess. Cut a round of parchment paper to fit on the bottom of each pan. This ensures that it will come out completely clean.

    rainbow cake
    Leah Maroney 
  10. Pour four of the batters into the four prepared pans. Smooth the top as best as you can. Bake at 360 F for 10 to 15 minutes.

    rainbow cake
     Leah MAroney
  11. Remove the cakes from the oven, cool in the pan for 2 minutes. Turn them onto a cooling rack to complete cooling. Peel the parchment paper off of the bottom of the cake. Prepare the pans again for the next four colors and repeat with the remaining batters.

    rainbow cake
     Leah Maroney
  12. Once the cakes have completely cooled (about 20 minutes) cover with plastic wrap and freeze on a flat surface.

    rainbow cake
     Leah Maroney
  13. When the cakes have been completely frozen, you can start assembling. Make sure you have the cakes in the order. Add the red layer to a cake board or just right onto your cake plate. Use a dollop of icing under the first layer to help it stick to the cake board or plate.

    rainbow cake
     Leah Maroney
  14. Add frosting on top of the layer. Do a thick edge so there won't be any gaps when it is stacked. Add another layer of cake and repeat with the icing. Continue until all of the layers have been stacked.

    rainbow cake
     Leah Maroney
  15. Do a crumb coat of the entire cake. Add more icing to the edges if you have gaps.

    rainbow cake
     Leah Maroney
  16. Add your final layer of frosting. Smooth or leave swirly. Style the bottom edge of the cake with more frosting if you wish.

    rainbow cake
     Leah Maroney
  17. Serve and enjoy!

    rainbow cake
    Leah Maroney 

Tip

  • Use gel food coloring for the best solid vibrant colors. Some of the regular food colorings are too watered down and won't give you the rich hues that you need.