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Sonic Birthday Cake

Sonic Birthday Cake Recipe

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Prep Time 30 minutes
Cook Time 25 minutes
Total Time 55 minutes
Servings: 12 servings
Calories: 554
Ingredients Method Notes

Ingredients
  

  • 2 cups (250g) all-purpose flour
  • 2 ½ teaspoons baking powder
  • ½ teaspoon salt
  • ½ cup (113g) unsalted butter, at room temperature
  • 1 ½ cups (300g) granulated sugar
  • 2 large eggs, at room temperature
  • 1 cup (240ml) whole milk
  • 2 teaspoons vanilla extract
  • 1 cup (226g) unsalted butter, at room temperature
  • 4 cups (480g) powdered sugar
  • 2 to 3 tablespoons whole milk
  • 2 teaspoons vanilla extract
  • Blue gel food coloring
  • Red gel food coloring
  • Golden ring sprinkles or yellow candy melts

Method
 

  1. Preheat oven to 350°F (180°C). Grease two 8-inch round cake pans and line the bottoms with parchment.
  2. Cream ½ cup butter and 1 ½ cups sugar until fluffy. Add eggs one at a time, then 2 teaspoons vanilla. Whisk dry ingredients, add in three parts alternating with 1 cup milk.
  3. Divide batter between pans and bake 22 to 25 minutes until a toothpick comes out with a few moist crumbs. Cool 10 minutes in pans, then transfer to a rack.
  4. Beat 1 cup butter until pale. Add 4 cups powdered sugar gradually, 2 tablespoons milk, and 2 teaspoons vanilla. Whip on high 2 minutes. Tint half blue and half red with gel colors.
  5. Level the cakes, fill with blue buttercream, stack, and apply a thin crumb coat of blue frosting. Chill 15 minutes.
  6. Frost with the remaining blue frosting, pipe or spread red decorations, and add golden ring sprinkles.

Notes

Let the cake layers cool completely before frosting, or the buttercream will melt and slide. If you want to bake ahead, wrap the unfrosted layers and freeze them up to 2 months.