Easy Superhero Layer Cake

Heat oven to 350°F (325°F for dark or nonstick pans). Make cake batter as directed on box. Divide batter equally among 3 bowls. Tint 1 bowl of batter with blue food color, 1 bowl with yellow food color and 1 bowl with red food color.

Spray 2 (8- or 9-inch) round cake pans with cooking spray. Line bottoms of pans with cooking parchment paper, if desired, to prevent sticking. Spoon 1/3 cup blue batter into center of each cake pan. Spoon 1/3 cup yellow batter into center of blue batter in each pan, followed by 1/3 cup red batter in each. Repeat with remaining batter until used up.

Bake as directed on box for 8- or 9-inch round cake pans. Cool in pans 10 minutes. Remove from pans to cooling rack. Cool completely, about 1 hour.

Tint 1 container frosting with blue food color to desired shade of blue. On serving plate, place 1 cake layer, rounded side down. Frost top of cake layer with part of the blue frosting. Top with second layer, rounded side up. Frost side and top of cake with remaining blue frosting.

In small bowl, tint three-fourths of the remaining container of frosting with yellow food color. Tint remaining frosting with red food color. Place yellow frosting in resealable food-storage plastic bag. Cut off small corner of plastic bag, and pipe diamond-shaped emblem on top of cake. Place red frosting in another resealable food-storage plastic bag. Cut off small corner of plastic bag, and pipe number or initials on cake.