Hooray for sprinkles! Get the party started with this fun and colorful rainbow sprinkle cake. White sour cream cake layers hold a flurry of funfetti inside.
I’m writing you from my happy place, which is in front of a big slice of cake that is filled with sprinkles inside and out. You probably already know this isn’t my first foray into sprinkle cake territory. In fact, I kind of consider myself a sprinkle cake veteran. Many years ago, on the first blog birthday of Sprinkle Bakes, I made what I often refer to as the original Sprinkle Cake. It’s a great little recipe, and I’ve made it countless times throughout the years. But I love this one just as much! It has the tang of sour cream, and a thick batter that suspends a whole galaxy of rainbow sprinkles inside. It’s like that old Girl Scout song “Make new friends but keep the old. One is silver and the other gold.” That sort of thing. Only with cake.
You may remember the Oreo Cake I recently made. I really enjoyed the flavor and texture of that cake. It did a good job of holding all those cookie pieces inside, and I just knew it would make a really great rainbow sprinkle cake. I’m happy to report that things went just as expected! The pale sour cream batter really shows off all those rainbow sprinkle colors. And the thick, fluffy batter suspends them throughout so they evenly speckle the interior. I’m in love!
Sprinkles: no need for fancy ones.
Regular old ice cream sprinkles (called ‘jimmies’) are perfect for baking in cake layers. They’re often used as an ice cream topping because they won’t melt away easily with moisture. You can find them with the ice cream toppings at your local grocery store, or in the baking section.
White Cake Flavoring is something I use when I want that old school bakery flavor. It gives the cake a rich vanilla flavor with something else that lingers in the background. The flavor reminds me of wedding cake, without as much overt almond flavor. Bakto makes a natural white cake flavor that I use often, and it’s great in this cake. If you don’t have room in your cabinet for another extract, just use pure vanilla extract mixed with just a smidge of almond extract.
This cake is stacked and frosted with white vanilla American buttercream frosting, which is an easy frosting recipe for bakers of every skill set. A classic!
DIY your sprinkle mix.
I used my own sprinkle mix for the outside of the cake. It’s a mixture of rainbow sprinkles, mixed with rainbow confetti, rainbow nonpareils, and sugar pearls. My advice is to stir up a combination of shapes and colors that make you happy. However, you can simply use the rainbow jimmies instead of a sprinkle mix.
Apply the sprinkles to the sides of the cake by pressing handfuls of sprinkles onto the sides. Use a baking sheet underneath to catch the excess. I find it easiest to press a handful at the base of the cake and slide my hand up the side of the cake. The tacky frosting will latch on to the sprinkles as you travel upward.
Pipe swirls of frosting, spaced about 2.5 inches apart, on the top edge of the cake. Then, toss on a few more sprinkles.
I wanted something fun for a cake topper, and just as eye-catching as the allsorts I used on my original sprinkle cake. My local grocery store had ‘gourmet lollipops’ at the checkout counter and I couldn’t resist them! Fun flavors like piña colada, cotton candy, blueberries and cream, blackberry, and candy apple made this cake extra special. I placed them on top of the cake beside swirls of frosting, with their sticks pointing, and meeting at, the center of the cake. If you go this route, then plan to buy a few extra lollipops to serve on the side. Not everyone will get a lollipop with their slice, and it’s best to have enough for every guest.
How cute is the ‘HOORAY’ cake topper? I’ve had it for ages. I just needed the right cake with the right vibe to show off all those glittery letters. This rainbow sprinkle cake is its perfect match! You can find it right here for purchase.
This colorful confection makes a great birthday cake – just add candles! The crumb is sturdy yet moist thanks to the sour cream in the batter. Serve this cake at room temperature, because the flavors and textures will be at their best!
- 8 inch cake pans, 3
- Large open star piping tip (French pastry tube)
- Piping bag
- Large offset spatula
Sprinkle cake layers
- 1 cup plus 2 tablespoons unsalted butter at room temperature
- 1 1/2 cups granulated sugar
- 3 cups all-purpose flour
- 1/2 teaspoon baking soda
- 1 1/4 teaspoons baking powder
- 1/2 teaspoon fine grain salt
- 5 egg whites at room temperature
- 1 1/2 teaspoons white cake flavor such as Bakto brand or 1 teaspoon vanilla extract plus 1/4 teaspoon almond extract
- 3/4 cup sour cream at room temperature
- 2/3 cup whole milk at room temperature
- 3/4 cup rainbow sprinkles ice cream type, called 'jimmies'
Vanilla buttercream and sprinkle coating
- 1 1/2 cups unsalted butter
- 6 cups confectioners’ sugar
- 2 teaspoons vanilla extract
- Milk or cream to thin
- 1 1/4 cup Mixed rainbow sprinkles jimmies, confetti, nonpareils, sugar pearls
- 8 round gourmet lollipops see blog post for shopping link
Sprinkle cake layers
- Preheat the oven to 350F.
- In the bowl of an electric mixer fitted with the whip attachment, beat the butter until creamy. Sprinkle in the granulated sugar gradually as you mix. Beat until light and fluffy.
- In a separate large mixing bowl, sift together the flour, baking soda, baking powder, and salt.
- In a 4-cup measure or batter bowl with a pour spout, whisk together the egg whites, vanilla, sour cream, and milk.
- Switch the mixer beater to the paddle attachment Beat 1/3 of the dry ingredients into the creamed butter mixture until just incorporated. Add in half of the liquid mixture; beat until combined. Continue adding 1/3 flour mixture followed by the remaining liquid; end with the flour mixture. Beat until the mixture is lightened in color and fluffy, about 2 minutes. Fold in the rainbow sprinkles.
- Coat three 8-inch cake pans with flour-based baking spray. Alternatively, grease and flour the pans.
- Divide the cake batter between the prepared pans. Smooth the top of the batter with the flat edge of the offset spatula.
- Bake the cakes for 25-30 minutes, or until the cakes spring back when pressed in the centers. Remove the cakes from the oven. If the tops are slightly rounded, flatten gently using a paper towel while the cakes are still warm. Do this gently and carefully as steam will escape as you press.
- Remove cakes to a wire rack to cool completely.
- Beat the butter in the bowl of an electric mixer fitted with the whip attachment. Whip until creamy. Add the confectioners’ sugar. Beat until combined. Add vanilla extract; mix well. Beat on medium speed adding milk or cream 1 tablespoon at a time, until the mixture thins to piping consistency. Beat on high speed until the frosting turns almost white in color, about 4 minutes with a timer set. Scrape down the bowl. Beat again on high speed. Remove 2/3 cup of frosting to a piping bag fitted with a large open star tip (also called French pastry tube).
- Fill two of the cooled cake layers with about 1/2 cup of the buttercream on each layer. Spread evenly. Stack them and then place the remaining cake layer on top. Generously cover the cake with the remaining buttercream using an offset spatula. Immediately coat the sides of the cake with sprinkles. To do this, place the cake on a baking sheet. Pick up handfuls of sprinkles and press them on from the bottom edge of the cake to the top. Repeat until the entire cake is coated Refrigerate the cake until the frosting firms.
- Using the reserved piping bag of frosting, pipe 8 large swirls on the top edge of the cake, well-spaced. Immediately top with sprinkles.
- Just before serving add a lollipop between each swirl on top of the cake with their sticks meeting at the top center of the cake.
- Serve this cake at room temperature. The cake's texture and flavors are completely developed at room temperature.