Confetti Cake with Vanilla-Sour Cream Frosting That Brings the Party to Every Bite

Confetti cake is the ultimate celebration dessert. It’s colorful, playful, and instantly reminds everyone of birthdays, joy, and good times. But when paired with a rich vanilla-sour cream frosting, it goes from fun to unforgettable. This cake has a soft, tender crumb and bursts of rainbow sprinkles baked right into the layers. The tangy, creamy frosting adds depth and keeps the sweetness balanced.

Whether you’re baking for a birthday, graduation, or just a weekend treat, this confetti cake with vanilla-sour cream frosting delivers big flavor and festive charm without needing a bakery.

What Makes Confetti Cake Special?

Confetti cake is essentially a fluffy vanilla cake with rainbow sprinkles mixed into the batter. As it bakes, the sprinkles melt slightly and spread out, leaving little pops of color and sweetness throughout the cake. It’s fun to look at and even better to eat.

You can use jimmies (long, soft sprinkles) for the best results. Avoid nonpareils or sanding sugar, which tend to bleed or disappear into the batter.

This recipe is made completely from scratch, but it’s just as simple as a box mix—with way more flavor and texture.

Ingredients for the Confetti Cake

Dry Ingredients

• 2 ½ cups all-purpose flour
• 2 ½ teaspoons baking powder
• ½ teaspoon baking soda
• ½ teaspoon salt

Wet Ingredients

• ¾ cup unsalted butter, softened
• 1 ¾ cups granulated sugar
• 4 large eggs, room temperature
• 1 tablespoon pure vanilla extract
• 1 cup buttermilk
• ½ cup sour cream
• ½ cup rainbow sprinkles (jimmies only)

The sour cream and buttermilk combo creates a soft, rich cake that stays moist for days. The vanilla adds a warm depth that pairs perfectly with the sweet sprinkles.

Making the Confetti Cake

Step 1: Prep Your Pans and Oven

Preheat the oven to 350°F. Grease and flour two 8-inch round cake pans or line them with parchment paper circles.

Step 2: Mix the Dry Ingredients

In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.

Step 3: Cream the Butter and Sugar

In a large mixing bowl, beat the softened butter and sugar together until light and fluffy. This takes about 3 to 4 minutes with a hand or stand mixer.

Step 4: Add Eggs and Vanilla

Add eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

Step 5: Combine Wet and Dry Mixtures

Mix the sour cream into the buttermilk. Add the dry ingredients to the butter mixture in three parts, alternating with the buttermilk-sour cream mixture. Begin and end with the dry ingredients. Mix on low until just combined.

Step 6: Fold in the Sprinkles

Gently fold in the rainbow sprinkles with a spatula. Be careful not to overmix so the sprinkles don’t bleed too much color.

Step 7: Bake the Cake

Divide the batter evenly between the prepared pans. Bake for 28–32 minutes, or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for 10 minutes, then transfer them to wire racks to cool completely before frosting.

Ingredients for Vanilla-Sour Cream Frosting

• 1 cup unsalted butter, room temperature
• 3 ½ cups powdered sugar, sifted
• 2 teaspoons vanilla extract
• ½ cup full-fat sour cream
• Pinch of salt

This frosting is silky and rich but not overly sweet. The sour cream adds a slight tang and smooth texture that balances perfectly with the cake.

Making the Frosting

Step 1: Beat the Butter

In a large mixing bowl, beat the butter on medium speed for about 2 minutes until creamy and pale.

Step 2: Add Powdered Sugar

Add the powdered sugar one cup at a time, beating on low until combined. Once all the sugar is in, increase to medium speed and beat until fluffy.

Step 3: Add Vanilla and Sour Cream

Mix in the vanilla extract and sour cream. Beat for another 2 to 3 minutes until smooth and spreadable. If it’s too thick, add a tablespoon of milk. If too soft, chill for 10 minutes before using.

Assembling the Cake

Once the cakes are fully cooled, level the tops if needed. Place the first layer on a cake board or serving plate. Spread a generous layer of frosting over the top. Add the second cake layer, then frost the top and sides.

You can keep the look rustic or smooth it out with an offset spatula. Add extra sprinkles on top or press them into the sides for a festive finish.

Tips for the Best Results

• Use room temperature ingredients for even mixing.
• Don’t overmix the batter after adding flour or sprinkles.
• Cool cakes completely before frosting to prevent melting.
• Use jimmies only for confetti-style color that holds up during baking.
• Chill the frosted cake for 30 minutes if you want clean slices.

When to Serve This Cake

This confetti cake is a hit at:

• Birthday parties
• Baby showers
• Graduation celebrations
• Holiday gatherings
• Weekend treats with family

It’s festive enough for special occasions but simple enough to make just because. The soft crumb, fun colors, and creamy vanilla-sour cream frosting make it a go-to recipe any time you want a cheerful, satisfying dessert.