Chocolate-Frosted Confetti Party Cake
January 5, 2026
A sprinkle-packed sheet cake with rich chocolate frosting and nonstop fun!
If you need a go-to birthday or party cake that everyone instantly gets excited about, this is it. This Chocolate-Frosted Confetti Party Cake starts with a soft, sprinkle-packed cake loaded with mini chocolate chips, then gets topped with a rich layer of chocolate frosting and a ton of sprinkles. It’s the kind of cake that feels like pure fun the second you set it on the table. When in doubt, this is always the cake I make.
Ingredient Notes
- White cake mix: White cake mix gives the best contrast for the sprinkles, but yellow cake mix works just as well.
- Sour cream: Adds moisture and keeps the cake soft without making it dense. Full-fat works best.
- Whole milk: Creates a richer cake texture. You can swap in 2% if needed.
- Mini chocolate chips: Mini chips distribute more evenly throughout the cake so you get chocolate in every bite.
- Sprinkles: Use jimmies-style sprinkles for mixing into the batter. Nonpareils can bleed color.
- Salted butter: Balances the sweetness of the chocolate frosting. If using unsalted, add a pinch of salt.
- Heavy cream: Start with less and add more to control the frosting consistency.
Why You’ll Love This Recipe
- Soft, sprinkle-packed cake with mini chocolate chips in every bite.
- Rich chocolate frosting that makes this feel like a true party cake.
- Made with a cake mix so it’s simple, reliable, and stress-free.
- Perfect for birthdays, parties, and celebrations where you need to feed a crowd.
- Easy to slice, easy to serve, and easy to decorate with sprinkles or candles.
Quick Prep Notes
Can I use a different cake mix flavor?
Yes. White cake mix gives you that classic confetti look, but yellow cake mix works just as well if that’s what you have. The texture and bake time stay the same.
Do I need to line the pan with parchment?
It’s not required, but it makes lifting the cake out and slicing it much easier, especially if you’re serving it for a party or transporting it.
Should the cake be completely cool before frosting?
Absolutely. If the cake is even slightly warm, the chocolate frosting will soften and slide instead of spreading smoothly.
Chocolate-Frosted Confetti Party Cake
Ingredients
Cake
- 1 box white cake mix
- 1 cup whole milk
- ½ cup sour cream
- ½ cup vegetable oil
- 3 large eggs
- ½ cup mini chocolate chips
- ¼ cup rainbow sprinkles
- ¼ cup chocolate sprinkles
Chocolate Frosting
- 1 cup salted butter, softened
- 3½ cups powdered sugar
- ½ cup cocoa powder
- 4–6 tablespoons heavy cream
- 1 teaspoon vanilla extract
Topping
- Extra rainbow sprinkles
- Extra chocolate sprinkles
Instructions
- Preheat your oven to 350°F. Spray a 9×13-inch pan with baking spray and line it with parchment paper for easy lifting later.
- In a large bowl, mix together the cake mix, milk, sour cream, oil, and eggs until smooth. Fold in the mini chocolate chips and both types of sprinkles. Pour the batter into the prepared pan and bake according to the box directions. Let the cake cool completely before frosting.
- To make the frosting, beat the softened butter until smooth and creamy. Add the powdered sugar, cocoa powder, 4 tablespoons of heavy cream, and vanilla. Mix until fluffy, adding more cream one tablespoon at a time until you reach your preferred consistency.
- Lift the cooled cake out of the pan and place it on a serving plate or cake board. Spread the chocolate frosting evenly over the top, or pipe a border around the edges for an extra touch. Finish with a generous sprinkle of rainbow and chocolate sprinkles.
- Slice and serve!
FAQ
Can I make this cake ahead of time?
Yes. You can bake the cake a day in advance and store it tightly covered at room temperature. Frost it the day of your event for the freshest look.
How should I store leftovers?
Cover the cake and store it in the refrigerator for up to 4 days. Let slices sit at room temperature for a few minutes before serving for the best texture.
Can I freeze this cake?
You can freeze the unfrosted cake, tightly wrapped, for up to 2 months. Thaw completely before frosting and decorating.
Can I use only one type of sprinkle?
Definitely. Rainbow sprinkles, chocolate sprinkles, or even themed sprinkles all work. Use what matches your celebration.
Is this cake good for birthdays and large parties?
Yes. This cake slices easily, serves a crowd, and has that classic birthday look and flavor that works for just about any celebration.
Sprinkle of Fun
Save this cake for the next birthday on your calendar! Add sprinkle-themed candles, blow up a bunch of balloons, and toss a little confetti around the room before serving. It’s an easy way to turn a simple cake into the ultimate celebration.
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