Directions

1. To make red cake layers: Heat oven to 350°F. Grease or spray two 8-inch round pans; place 8-inch round piece cooking parchment paper in bottom of each pan. Grease or spray parchment paper. In large bowl, beat red cake layer ingredients with electric mixer on low speed 30 seconds, then on high speed about 2 minutes or until smooth. Spread in pans. Bake 29 to 34 minutes or until top springs back when lightly touched. Cool 10 minutes; run knife around sides of pans to loosen cakes. Gently remove from pans to cooling rack; remove parchment paper. Cool completely, about 30 minutes. Flatten cake layers by trimming off rounded tops. Cut layers in half horizontally to make 4 thin red layers. In 1 layer, cut small round out of center, using 4-inch biscuit cutter. Wrap and freeze 1 thin layer and the layer that was cut out of; save for another use.
2. To make blue cake layer: Heat oven to 350°F. Grease or spray 8-inch round pan; place 8-inch round piece cooking parchment paper in bottom of pan. Grease or spray parchment paper. In medium bowl, beat all blue cake layer ingredients except sprinkles with electric mixer on low speed 30 seconds, then on high speed about 2 minutes or until smooth. Fold sprinkles into batter. Spread in pan. Bake 29 to 34 minutes or until top springs back when lightly touched. Cool 10 minutes; run knife around side of pan to loosen cake. Gently remove from pan to cooling rack; remove parchment paper. Cool completely, about 30 minutes. Flatten cake layer by trimming off rounded top. Do not cut in half horizontally. Cut small round out of center, using 4-inch round biscuit cutter. Wrap and freeze 4-inch round; save for another use.
3. To make white cake layer: Heat oven to 350°F. Grease or spray 8-inch round pan; place 8-inch round piece cooking parchment paper in bottom of pan. Grease or spray parchment paper. In medium bowl, beat white cake layer ingredients with electric mixer on high speed about 2 minutes or until smooth. Spread in pan. Bake 29 to 34 minutes or until top springs back when lightly touched. Cool 10 minutes; run knife around side of pan to loosen cake. Gently remove from pan to cooling rack; remove parchment paper. Cool completely, about 30 minutes. Flatten cake layer by trimming off rounded top. Cut layer in half horizontally to make 2 thin white layers. In 1 layer, cut small round out of center, using 4-inch biscuit cutter. Wrap and freeze the layer that was cut out of; save for another use.
4. To assemble cake: Place 1 red cake layer on cake stand or serving platter; spread 1/3 cup frosting on top. Top with 1 white cake layer; spread 1/3 cup frosting on top. Top with second red cake layer; spread 1/3 cup frosting on top. Gently top with blue layer. Carefully spread thin layer of frosting on cut edge inside of blue cake layer. Gently insert white 4-inch cake round; top with frosting and then red 4-inch cake round; press slightly. Frost side and top of cake using remaining frosting. Top with sprinkles. Store loosely covered in refrigerator.