What’s in Rainbow Birthday Cake?
This Rainbow Cake is made with all the classics—butter, sugar, eggs, and your favorite vanilla extract. And the magic ingredient for those vibrant colors? Gel food coloring!
Flour: All-purpose flour is best for this cake recipe. Sugar: Use granulate sugar to add sweetness. Leavening: Use both baking soda and baking powder to make this cake rise. Salt: Just a bit to balance the sweetness. Buttermilk: Let the buttermilk sit at room temperature, so it mixes well with the other ingredients. This creates an incredibly moist cake. Butter: Unsalted butter that’s just starting to melt is the sweet spot. Make sure you have enough for the vanilla frosting too! Eggs: Large eggs work best. Vanilla: Pure vanilla extract gives this white cake its classic flavor. Food Coloring: Those vibrant rainbow colors have to come from somewhere! Start with one or two drops, then add more to get your desired shade.
Pro Tip: No buttermilk? That’s okay! You can get that tangy flavor from a combo of common pantry ingredients. Try mixing a tablespoon of white vinegar (or lemon juice) with one cup of milk to create the perfect substitute.
Variations on Rainbow Layer Cake
There are so many fun ways to decorate the outside and the top of the cake! I love the simple white frosting with rainbow sprinkles to hint at the surprise to come! You could also opt for an ombre effect, with each color corresponding to the colorful layers inside. Garnish with rainbow sprinkles or make a crumb coat with the crumbled-up leftover cake pieces from leveling the cakes. Or have even more fun and swirl all of the frosting colors together for a tie-dye look!
How to Make Ahead and Store Rainbow Theme Cake
The cake layers can be baked in advance, wrapped in plastic, and stored for up to 2 days at room temperature, or up to 3 months in the freezer. Let the cake layers defrost at room temperature. The buttercream frosting can be stored in an airtight container in the refrigerator for up to 1 week. Let come to room temperature before coloring and using. Store leftover slices of rainbow cake tightly wrapped in plastic wrap or covered with a cake dome at room temperature for up to 2 days or in the refrigerator for up to 4 days.
How to Freeze
Freeze the rainbow cake whole or cut it into individual slices tightly wrapped in plastic wrap for up to 1 month. Let thaw overnight in the refrigerator before enjoying.
More Layer Cake Recipes We Love
Red Velvet Cake Yellow Cake with Chocolate Frosting Funfetti Cake Chocolate Cake with Chocolate Frosting White Cake with Strawberry Filling German Chocolate Cake Carrot Cake Black Magic Cake with White Icing Hummingbird Cake
