This Rainbow Layer Cake is a stunning and festive dessert that features multiple layers of vibrantly colored vanilla cake, all stacked high and coated with a smooth, fluffy buttercream. Perfect for birthdays, celebrations, or any time you want to add a splash of color to your table, this cake is as delightful to look at as it is to eat.

Why You’ll Love This Recipe

This Rainbow Layer Cake is a guaranteed showstopper. It offers the perfect balance of visual appeal and delicious flavor. Each slice reveals bright, even layers of cake in red, orange, yellow, green, blue, and purple, making it ideal for parties or celebrations. Despite its eye-catching appearance, the recipe is surprisingly easy to follow with a straightforward process. It’s a classic vanilla cake that remains moist and tender, and the creamy buttercream frosting complements the sweetness of the layers beautifully.

Ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

All-purpose flour
Baking powder
Baking soda
Salt
Unsalted butter
Granulated sugar
Egg whites
Whole milk
Pure vanilla extract
Gel food coloring (red, orange, yellow, green, blue, purple)
Powdered sugar (for frosting)
Heavy cream (for frosting)

Directions

Preheat your oven to 350°F (175°C). Grease and line six 8-inch round cake pans, or work in batches if needed.
In a bowl, whisk together the flour, baking powder, baking soda, and salt.
In a separate large bowl, cream the butter and sugar until light and fluffy.
Add the egg whites, one at a time, mixing well after each addition. Stir in the vanilla extract.
Alternately add the flour mixture and milk to the wet ingredients, beginning and ending with the flour mixture.
Divide the batter evenly into six bowls. Tint each with a different color of gel food coloring.
Pour each colored batter into its own prepared cake pan and smooth the tops.
Bake for 15–18 minutes or until a toothpick inserted in the center comes out clean.
Let the cakes cool in the pans for 10 minutes before transferring to wire racks to cool completely.
For the buttercream frosting, beat butter until creamy, then gradually add powdered sugar and heavy cream, beating until fluffy.
Level each cake layer if needed, then stack them in the color order of your choice, spreading frosting between each layer.
Frost the outside and top of the cake with remaining buttercream. Chill slightly before slicing for the cleanest cuts.

Servings and timing

This Rainbow Layer Cake serves approximately 12–16 people.
Preparation Time: 45 minutes
Baking Time: 18 minutes
Cooling and Frosting Time: 1 hour
Total Time: About 2 hours

Variations

Chocolate Rainbow Cake: Add a touch of cocoa powder to the base batter for a chocolatey version.
Lemon-flavored Layers: Add lemon zest to the batter for a fresh citrus twist.
Fruity Frosting: Mix fresh fruit puree (such as raspberry or strawberry) into the frosting for added flavor and color.
Mini Cakes: Use smaller pans or cut the layers to make mini versions of this rainbow cake.

storage/reheating

Store the assembled cake in the refrigerator, covered, for up to 5 days. Allow it to come to room temperature before serving for best texture and flavor.
Slices can be individually wrapped and frozen for up to 2 months. Thaw in the refrigerator overnight or at room temperature for a few hours before eating.
Do not reheat the cake in the microwave, as the frosting may melt or separate.

FAQs

How do I get vibrant colors in the cake layers?

Use gel food coloring rather than liquid food coloring. Gel provides more intense color without altering the consistency of the batter.

Can I use a box cake mix instead?

Yes, you can use white cake mix as a shortcut. Divide and color the batter just as you would with homemade.

How do I prevent the cake layers from sticking?

Make sure to grease and line your pans well with parchment paper circles to ensure easy removal.

Can I make this cake ahead of time?

Yes, you can bake the layers a day in advance. Wrap them tightly in plastic and store at room temperature. Assemble and frost the next day.

What frosting works best for a rainbow cake?

A classic vanilla buttercream or cream cheese frosting works well. Make sure it’s sturdy enough to hold the layers in place.

How can I make the layers more even?

Use a kitchen scale to divide the batter equally among the pans and level the tops after baking with a serrated knife.

Is this cake suitable for kids’ parties?

Absolutely. It’s colorful, festive, and fun—ideal for birthday parties or any celebration with children.

Can I make this gluten-free?

Yes, substitute the flour with a 1-to-1 gluten-free baking flour. Results may vary slightly depending on the brand.

How should I transport the cake?

Chill the cake before transporting to ensure the layers stay intact. Use a cake carrier or box for protection.

Can I use natural food coloring?

You can, but natural colors may not be as vibrant and can fade during baking. Test beforehand for desired results.

Conclusion

This Rainbow Layer Cake is more than just a dessert—it’s a celebration in every slice. Whether for a birthday, holiday, or special event, this cake brings joy to any occasion with its eye-catching layers and delicious taste. With a simple vanilla base and fluffy buttercream, it’s as satisfying to eat as it is impressive to serve