Rainbow Layer Cake
Ingredients
For the Cake:
- Baking spray
- 2 15.25-ounce packages Duncan Hines Classic White Cake Mix
- 1-1/2 cups water
- 6 eggs
- 2/3 cup vegetable oil
- 2 tsp. vanilla extract
- Red, orange, yellow, green, blue and purple food coloring
For the Buttercream Frosting:
- 3 cups unsalted butter, softened
- 1/4 cup heavy whipping cream
- 4 tsp. vanilla extract
- 1 tsp. salt
- 1 32-ounce bag confectioners' sugar
Instructions
To prepare the cake:
- Pre-heat oven to 350°F.
- Spray three 9-inch round cake pans with baking spray.
- In a large bowl, with an electric mixer at low speed, blend cake mix, water, eggs, oil and vanilla until moistened; continue to beat, at medium speed, for 2 additional minutes.
- Divide batter evenly into 6 bowls, about 1 1/2 cups each; add 1/2 teaspoon red food coloring to one bowl, 1/4 teaspoon yellow to another and 1/4 teaspoon orange to a third bowl of batter; stir each until blended.
- Pour each into separate pans; place in pre-heated oven and bake 14 to 16 minutes, until toothpick comes out clean; cool 10 minutes; remove from pans to cooling racks and cool completely.
- Meanwhile, add 1/2 teaspoon blue food coloring to one of the remaining bowls of batter, 1/2 teaspoon green to another and 1/2 teaspoon purple to the final bowl; stir until blended. refrigerate until ready to bake.
- Wash, dry and spray cake pans with baking spray; pour each remaining color into separate pans and bake 14 to 16 minutes, until toothpick comes out clean; cool 10 minutes; remove from pans to cooling racks and cool completely.
To prepare the buttercream frosting:
- In a large bowl, with an electric mixer, on low speed, beat butter, heavy cream, vanilla and salt until blended; about 1 minute.
- Slowly beat in confectioner's sugar until smooth.
- Increase speed to medium and beat until light and fluffy; about 3 to 5 minutes.
To assemble the rainbow layer cake:
- Trim rounded tops off cakes, to level, if necessary.
- Place purple cake layer on cardboard round; spread with about 1/2 cup frosting; top with blue cake layer and press lightly to adhere; repeat with green, yellow, orange and red cake layers.
- Spread a light coating of frosting all over sides of cake; refrigerate 15 minutes.
- Remove from refrigerator and frost with remaining frosting.
- Transfer cake to a serving plate.
