Make cake. Prepare batter following recipe directions. Divide batter into four equal portions, 2 1/4 cups each. Tint one portion each rose, royal blue, yellow and orange. Bake and cool cakes. Use cake leveler to level cakes to 1 1/4 in. high.
Prepare buttercream icing according to recipe directions. Stack and fill for a 4-layer cake, 5 in. high. Use spatula and icing to ice cake smooth.