Rainbow Sprinkles Polka Dot Surprise Cake

Unveil a delightful surprise with the Rainbow Sprinkles Polka Dot Surprise Cake, perfect for adding a splash of color and fun to any celebration. This cake features hidden colorful polka dots made from cake balls inside a classic vanilla cake, all wrapped up in a vibrant sprinkle-covered frosting. It’s an ideal choice for birthdays, parties, or any event that calls for a festive touch.


For the Cake Balls:
  • 1 box white cake mix
  • Food coloring in assorted colors (yellow, green, pink, blue, purple)
  • 2 cups buttercream frosting
For the Classic Vanilla Cake:
  • 1 box white cake mix
  • 1 cup all-purpose flour
  • 1 cup granulated sugar
  • ¾ tsp salt
  • 3 large eggs, room temperature
  • 1 ⅓ cups water
  • 2 tbsp vegetable oil
  • 8 oz sour cream
  • 2 tsp pure vanilla extract
  • ½-1 tsp almond extract (optional)
For the Frosting:
  • 2 cups unsalted butter, softened
  • 8 cups powdered sugar
  • ½ cup heavy cream
  • 2 tsp vanilla extract
For the Decoration:
  • 2 cups assorted sprinkles


  1. Make Cake Balls:
    • Prepare the white cake mix according to package instructions. Divide the batter among several bowls, adding different food coloring to each bowl to create vibrant colors. Bake in small pans or as cupcakes, then allow to cool.
    • Once cooled, crumble the cakes into fine pieces and mix each color separately with some buttercream frosting until it holds together. Form this mixture into small balls and refrigerate on a lined baking sheet for 1-2 hours until firm.
  2. Bake the Cake:
    • Prepare another batch of white cake mix, enhancing it with flour, sugar, salt, eggs, water, oil, sour cream, vanilla, and almond extract for added richness and flavor.
    • Pour a base layer of batter into three 6-inch cake pans. Place the chilled cake balls randomly into the batter, ensuring they don’t touch the bottom or sides of the pan. Cover the balls with more batter.
    • Bake at 350°F for 22-26 minutes or until a toothpick comes out clean. Let the cakes cool completely.
  3. Frost and Decorate:
    • Slice off the domed tops of each cooled cake layer to create flat surfaces. Stack the layers with frosting between each and cover the entire cake with a thin crumb coat. Chill briefly if necessary.
    • Apply a generous final layer of frosting, then cover the cake with sprinkles, pressing them gently into the sides and top to adhere.


  • Firm Cake Balls: Ensure the cake balls are sufficiently chilled and firm before embedding them into the batter, preventing them from dissolving during the baking process.
  • Decoration Technique: Use a turntable for easier frosting application, and place a large tray underneath to catch any falling sprinkles.


The Rainbow Sprinkles Polka Dot Surprise Cake is not only a feast for the taste buds but also a visual spectacle that promises to be the centerpiece of your celebration. With its hidden surprises and colorful appearance, this cake is sure to enchant guests and make your special occasion even more memorable. Enjoy the process of creating this joyful masterpiece and the delightful reactions it will undoubtedly provoke!

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