Buttercream icing is recommended for cake decorating due to its taste and workability. Paste food coloring works best when added gradually to icing and mixed thoroughly. Cakes should be leveled and smoothed with icing before decorating. Decorating bags make it easy to apply icing and create decorations using different tips. Buttercream icing is a popular recipe that is light and fluffy when the shortening and sugar are creamed together and liquid is gradually incorporated.