Celebrate birthdays and special occasions with this Funfetti Sheet Cake. Soft, moist, and studded with rainbow sprinkles, it’s finished with a creamy strawberry cream cheese frosting for a colorful, crowd-pleasing dessert that serves about 18.


The Secret To a Soft, Fluffy Cake
A key trick makes this cake especially tender: adding boiling water to the batter. It thins the batter but delivers a moist, airy crumb. The result is a light sheet cake that’s fun to eat thanks to the rainbow sprinkles. The recipe is simple to prepare and yields plenty of servings, so it’s ideal for parties and larger gatherings.
Ingredients and Substitutions
Below are the ingredients for the cake and frosting, plus a few substitution suggestions.
For the Sheet Cake:
- 3 cups all-purpose flour – Provides structure. For a slightly lighter texture, substitute cake flour.
- 1 ¼ teaspoons baking powder + 2 ½ teaspoons baking soda – The baking powder helps the cake rise; the baking soda balances the acidity of the buttermilk and contributes to a tender crumb.
- 1 teaspoon salt – Balances sweetness and enhances flavor.
- 2 cups granulated sugar – Sweetens and encourages slight browning.
- 3 large eggs – Add structure, richness, and stability.
- ½ cup canola oil – Keeps the cake moist; swap for any neutral oil or melted butter for a richer flavor.
- 1 cup buttermilk – Adds tenderness and subtle tang. If you don’t have buttermilk, you can use a buttermilk substitute made from milk and an acid.
- 2 ½ teaspoons pure vanilla extract – Classic flavoring; imitation vanilla also works.
- 1 cup boiling water – This thins the batter and creates a moist, fluffy cake.
- ¾ cup rainbow sprinkles – Use jimmies-style sprinkles to minimize color bleeding.
For the Strawberry Cream Cheese Frosting:
- 1 cup unsalted butter – Softened so it mixes smoothly; provides body and flavor.
- 8 ounces cream cheese – Softened; full-fat gives the creamiest result.
- 2 ½ cups powdered sugar – Sweetens and thickens; sift if lumpy.
- ½ cup strawberry preserves – Adds fruity flavor and a pale pink color; raspberry or cherry preserves are good alternatives.

How To Make Funfetti Sheet Cake
Prepare a thin batter by adding boiling water, bake until golden, then cool completely before frosting. Finish with strawberry cream cheese frosting and extra sprinkles for a festive look.
Bake the Funfetti Sheet Cake
- Mix the dry ingredients: In a large bowl combine flour, baking powder, baking soda, salt, and sugar.
- Add the wet ingredients: Whisk in the eggs, oil, buttermilk, and vanilla until smooth and lump-free.
- Pour in the boiling water: Add the hot water carefully and whisk until the batter is fully combined and thin.

- Fold in the sprinkles: Gently fold them in with a spatula to avoid color bleeding.
- Bake: Pour batter into a parchment-lined and greased 9×13-inch pan. Bake in a 350°F (175°C) oven for about 30 minutes. Let the cake cool in the pan for at least 1 hour before frosting.

Make the Strawberry Cream Cheese Frosting
- Beat butter and cream cheese: In a bowl, beat softened butter and cream cheese on low speed until smooth.
- Add sugar and preserves: Mix in powdered sugar and strawberry preserves, beating until light and fluffy. For a brighter color, add a drop of pink food coloring if desired.

Frost and Decorate
- Frost: Once the cake is completely cool, spread the frosting evenly with an offset spatula.
- Decorate: Generously top with rainbow sprinkles for the classic Funfetti look.
- Serve: Slice into squares, serve, and enjoy.

Essential Recipe Tips
Use jimmies-style sprinkles. They hold their color better and are less likely to bleed into the batter.
Don’t skip the boiling water. The thin batter it creates is responsible for the cake’s moist, tender crumb.
Cool completely before frosting. Frosting warm cake will melt it and cause the topping to slide.
Make It A Meal
Pair the cake with a fruity beverage for a festive pairing, such as a light strawberry drink to complement the frosting.

Funfetti Sheet Cake
Equipment
- 9×13-inch baking pan
- large mixing bowl
- whisk
- measuring cups and spoons
- spatula
- wire rack
- hand mixer or stand mixer
- offset spatula
- knife or cake cutter
Ingredients
FOR THE SHEET CAKE:
- 3 cups all-purpose flour
- 1 ¼ teaspoons baking powder
- 2 ½ teaspoons baking soda
- 1 teaspoon salt
- 2 cups granulated sugar
- 3 large eggs
- ½ cup canola oil
- 1 cup buttermilk
- 2 ½ teaspoons vanilla extract
- 1 cup boiling water
- ¾ cup rainbow sprinkles
FOR THE STRAWBERRY CREAM CHEESE FROSTING:
- 1 cup unsalted butter, softened
- 8 ounces cream cheese, softened
- 2 ½ cups powdered sugar
- ½ cup strawberry preserves
FOR DECORATING:
- ½ cup rainbow sprinkles
Instructions
Make the Funfetti Sheet Cake:
- Preheat the oven to 350°F (175°C). Line a 9×13-inch pan with parchment paper, leaving an overhang for easy removal.
- In a large bowl, whisk flour, baking powder, baking soda, salt, and sugar.
- Add eggs, oil, buttermilk, and vanilla. Whisk until the batter is smooth with no dry spots.
- Carefully pour in the boiling water and whisk until fully combined. The batter will be thin—that’s expected.
- Fold in the rainbow sprinkles gently to limit color bleed.
- Pour the batter into the prepared pan. Bake for about 30 minutes or until the cake is golden and springs back when pressed.
- Cool in the pan for 1 hour before transferring to a wire rack and frosting.
Make the Strawberry Cream Cheese Frosting:
- Beat the softened butter and cream cheese together on low speed until smooth.
- Add powdered sugar and strawberry preserves. Beat until the frosting is creamy and fluffy. Add a drop of pink food coloring if you want a more vivid color.
Frost and Decorate:
- When the cake is completely cool, spread the frosting evenly with an offset spatula.
- Top with a generous layer of rainbow sprinkles.
- Cut into squares and enjoy.
Nutrition
Nutrition information is an approximation.
Additional Info
Funfetti Sheet Cake Recipe FAQs
Yes. Two 8-inch round pans can be used instead of a 9×13 pan, but the baking time will be shorter. Begin checking around 20 minutes and bake until a toothpick comes out clean.
This is normal. The hot water thins the batter and helps produce a moist, tender cake—it’s the secret to the texture.
Absolutely. Chocolate or vanilla buttercream, or another favorite frosting, will also pair nicely with this cake.
More Desserts
- Creamy & Cozy Instant Pot Rice Pudding
- Raspberry Oat Bars
- Brioche Cinnamon Rolls


