Rainbow Cake

Vanilla layered rainbow cake

Abby Mercer / The Spruce

Prep: 45 mins
Cook: 35 mins
Total: 80 mins
Servings: 12 servings
Nutritional Guidelines (per serving)
1412 Calories
55g Fat
221g Carbs
9g Protein
See Full Nutritional Guidelines Hide Full Nutritional Guidelines
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Nutrition Facts
Servings: 12
Amount per serving
Calories 1412
% Daily Value*
Total Fat 55g 70%
Saturated Fat 21g 103%
Cholesterol 64mg 21%
Sodium 1016mg 44%
Total Carbohydrate 221g 81%
Dietary Fiber 1g 3%
Total Sugars 170g
Protein 9g
Vitamin C 0mg 2%
Calcium 210mg 16%
Iron 4mg 24%
Potassium 239mg 5%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

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 cups 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 large egg whites

  • 4 to 5 pounds vanilla frosting

Steps to Make It

  1. Gather the ingredients.

    Rainbow Cake ingredients

    The Spruce / Abby Mercer

  2. Beat the sugar and butter until creamy and whipped, about 10 minutes.

    butter and sugar creamed together in a bowl

    The Spruce / Abby Mercer

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

    dry cake ingredients in a bowl

    The Spruce / Abby Mercer

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

    butter with drying ingredients in a bowl

    The Spruce / Abby Mercer

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

    batter in a bowl

    The Spruce / Abby Mercer

  6. Beat the egg whites until they form stiff peaks.

    beat egg whites in a bowl

    The Spruce / Abby Mercer

  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.

    batter in a bowl

    The Spruce / Abby Mercer

  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.

    batter of different colors in bowls

    The Spruce / Abby Mercer

  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.

    prepared cake pans

    The Spruce / Abby Mercer

  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.

    cake batter in a cake pans

    The Spruce / Abby Mercer

  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.

    cake on cooling racks

    The Spruce / Abby Mercer

  12. Once the cakes have completely cooled (about 20 minutes), trim the tops to ensure even layers.

    cut the the tops of the cake to make them level

    The Spruce / Abby Mercer

  13. Cover with plastic wrap and freeze on a flat surface.

    cakes wrapped in plastic wrap

    The Spruce / Abby Mercer

  14. When the cakes have been completely frozen, you can start assembling. Make sure you have the cakes in the order. Add the purple 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.

    cake on a cake board

    The Spruce / Abby Mercer

  15. 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.

    colorful cakes with icing in between

    The Spruce / Abby Mercer

  16. Do a crumb coat of the entire cake. Add more icing to the edges if you have gaps.

    crumb coat of the entire cake

    The Spruce / Abby Mercer

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

    cake covered in icing

    The Spruce / Abby Mercer

  18. Serve and enjoy!

    Rainbow Cake slice

    The Spruce / Abby Mercer

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.

6 Inch Cake Pans

For a taller cake, you can use 6 inch cake pans. These thicker layers will take about 20-25 minutes to bake.