Buttery vanilla layer cake filled to the brim with rainbow sprinkles and finished off with sweet vanilla frosting. Pictured cake is 9 inches; for thicker cakes, use 8-inch pans. Review the recipe notes and bring all ingredients to room temperature before you begin.
- 3 and 3/4 cups (443g) cake flour* (spoon & leveled)
- 1 teaspoon baking powder
- 1 teaspoon baking soda
- 1 teaspoon salt
- 1 and 1/4 cups (2.5 sticks; 290g) unsalted butter, softened to room temperature
- 2 cups (400g) granulated sugar
- 1/3 cup (80ml) vegetable oil
- 4 large eggs, at room temperature*
- 2 large egg whites, at room temperature*
- 3 teaspoons (15ml) pure vanilla extract
- 1 and 1/2 cups (360ml) buttermilk, at room temperature*
- 3/4 cup (135g) rainbow sprinkles*
- 1 and 1/2 cups (3 sticks; 345g) unsalted butter, softened to room temperature
- 5 and 1/2 cups (650g) confectioners’ sugar
- 1/3 cup (80ml) heavy cream, at room temperature
- 3 teaspoons (15ml) pure vanilla extract (or use clear imitation vanilla extract for stark white frosting)
- 1/8 teaspoon salt
- optional: additional sprinkles for garnish
- Preheat oven to 350°F (177°C). Grease three 8-inch or 9-inch cake pans, line with parchment paper rounds, then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. (If it’s helpful, see this parchment paper rounds for cakes video & post.)
- Make the cake: Whisk the cake flour, baking powder, baking soda, and salt together in a large bowl. Set aside.
- Using a handheld or stand mixer fitted with a paddle attachment, beat the butter and sugar together on high speed for 5 full minutes until completely creamed together and fluffy. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Add the oil and beat for 1 minute until combined. Add the eggs, egg whites, and vanilla extract and beat on medium-high speed until combined. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed.
- Add dry ingredients and buttermilk in three additions, mixing after each addition just until incorporated. Do not over-mix this batter. The batter will be velvety and thick. Gently fold in the sprinkles. Pour and spread the batter evenly into each cake pan.
- Bake for around 25–26 minutes or until the cakes are baked through. (8-inch cakes may take about 27–28 minutes.) Tent the cakes with foil after about 15 minutes to prevent the sides and top from over-browning. To test for doneness, insert a toothpick into the center of the cake. If it comes out clean, it’s done.
- Allow cakes to cool in the pans set on a wire rack for 20 minutes. Run a knife around the edges and then remove cakes from pans. Place cakes directly on wire racks to cool completely. The cakes must be completely cool before frosting and assembling.
- Make the frosting: In a large bowl using a hand-held mixer or stand mixer fitted with a whisk or paddle attachment, beat the butter on medium speed until creamy, about 2 minutes. Add confectioners’ sugar, cream, vanilla extract, and salt. Beat on low speed for 30 seconds and then switch to high speed and beat for 2 minutes. Add more confectioners’ sugar if frosting seems too thin; more cream if frosting is too thick; or an extra pinch of salt if frosting is too sweet.
- Assemble cake + apply crumb coat: First, using a large serrated knife, slice a thin layer off the tops of the cakes to create a flat surface. Discard (or crumble over ice cream!). Place one cake layer on your cake stand or serving plate. Using a large icing spatula or small offset spatula, evenly cover the top with about 1 cup (about 250g) of frosting. Repeat with second cake layer, 1 more cup of frosting, and then the top cake layer. Spread a thin layer of frosting on the top and around the sides as a crumb coat. Run a bench scraper around the cake to smooth out crumb coat. Chill uncovered in the refrigerator for at least 30 minutes and up to 3 hours to set the crumb coat.
- Spread the remaining frosting all over the top and sides. Garnish with extra sprinkles, if desired.
- Serve cake immediately, or if you need to store it for a few hours, place it in a cake carrier at room temperature for up to 4 hours. For longer storage, refrigerate covered cake for up to 1 day. Cake is best served at room temperature, though, so if it’s been refrigerated, let it sit out at room temperature for 30 minutes before serving.
- Cover leftover cake tightly and store it in the refrigerator for 5 days. Again, I like using a cake carrier for storing and transporting.
- Make Ahead & Freezing Instructions: The cake layers can be baked, cooled, and covered tightly at room temperature overnight. Likewise, the frosting can be prepared and then covered and refrigerated overnight. When ready to decorate, let the frosting sit at room temperature to slightly soften for 15 minutes, then give it one more mix with the mixer on medium speed for about 1 minute before frosting cake. (Add a splash of cream to thin out frosting if needed.) See step 10 if you want to store the frosted/decorated cake before serving it. Frosted cake or unfrosted cake layers can be frozen for up to 2–3 months. Thaw overnight in the refrigerator and bring to room temperature before decorating/serving. See how to freeze cakes for detailed instructions.
- 2022 Update: Recipe above was slightly updated in 2022. Old version used to call for 3 sticks (about 345g) of butter and no oil. The slight reduction of butter and added oil makes a moister cake, but feel free to use the old version. Also, the extra egg whites are now added when you add the whole eggs. You used to have to whip them separately until soft peaks form and then fold them in before adding the sprinkles. This step isn’t really necessary because we’re using a little oil and cake flour now. (See next Note.)
- Flour: Recipe used to call for sifted all-purpose flour instead of cake flour. Recipe was updated in 2022 to use the SAME amount of cake flour instead. You can use either, but know that the cake is slightly lighter using cake flour. If you use all-purpose flour, you must sift it, otherwise your cake will be heavy. You could also use 3 and 3/4 cups (443g) of this cake flour substitute, which is sifted all-purpose flour + some cornstarch.
- Eggs: 4 whole eggs provide structure, moisture, and richness. 2 extra egg whites keep the cake light. I don’t recommend using 5 whole eggs as a replacement; stick to the 4 eggs + 2 egg whites combination.
- Buttermilk: If you don’t have buttermilk, you can make a DIY sour milk substitute. Add 1 Tablespoon of white vinegar or lemon juice to a liquid measuring cup. Then add enough whole milk to the same measuring cup until it reaches 1 and 1/2 cups. (In a pinch, lower-fat or nondairy milks work for this soured milk, but the cake won’t taste as moist or rich.) Stir it around and let sit for 5 minutes. The homemade “buttermilk” will be somewhat curdled and ready to use in the recipe.
- Sprinkles: Avoid using sprinkles that will dye your batter. Steer clear from nonpareils, which are the little balls. The pictured cake uses Betty Crocker “Parlor Perfect” rainbow sprinkles, which I find in my regular grocery store. I also like to use these rainbow jimmies or pastel colored quins. Note that naturally colored sprinkles may lose their color in cake batter.
- Chocolate Frosting: Use the frosting from this piñata cake recipe. It makes enough for this size cake.
- Amount of Cake Batter & Other Size Cakes: This recipe yields nearly 8 cups of batter, which is helpful if you need it for different Cake Pan Sizes & Conversions. For a 1-layer cake, 12×17-inch sheet cake, or 6-inch layer cake, see the list of recipe links in the post, above the recipe card. For a 2-layer cake, divide batter between 2 9-inch cake pans instead of 3. (This is too much batter for 2 8-inch pans.) Increase bake time to about 30 minutes and use a toothpick to test for doneness. For a Bundt cake, use a 10–12-cup generously greased Bundt pan and bake for about 60 minutes, or until a toothpick inserted in the center comes out clean. There is too much batter for a 9×13-inch quarter sheet cake. I have 2 recipes on my website that would work for a 9×13-inch sprinkle cake. You could use this light and fluffy white cake recipe and fold 1/2 cup (about 90g) sprinkles into the batter before pouring into the pan. See those recipe Notes for a 9×13-inch cake. Or you can use this buttery sprinkle sheet cake recipe. See those recipe Notes for a 9×13-inch cake.
- Cupcakes: Use this batter for 3 dozen sprinkle cupcakes. Fill cupcake liners about 2/3 full to avoid over-flowing. Or use my confetti sprinkle cupcakes or funfetti cupcakes recipes.
Keywords: confetti birthday cake