Bake your favorite 2-layer cake recipe or mix in cake pan. Cool cake in pan on wire rack 10 minutes. Remove from pan and cool completely. Arrange on foil-wrapped cake board. Spatula ice in white buttercream.
Randomly decorate tip 4 bead hearts in rose, violet, yellow green and blue buttercream on cake top and sides. Add tip 18 dark rose shell top border. Pipe tip 16 dark rose shell bottom border; overpipe with tip 86 zigzag ruffle. Insert pick in cake top.