Bake cakes.
Prepare cake batter following recipe instructions. Combine Kelly Green and Black icing colors to get light, medium and dark green colors shown. Tint three cups batter light green, six cups batter medium green and 3 cups batter dark green using color combinations provided. Transfer batter to 16 in. decorating bags.
Prepare pan with dividing ring. Starting in center, fill center ring ½ full with medium green batter, next ring ½ full with light green batter and outer ring ½ full with medium green batter. Carefully remove dividing ring; rinse and dry thoroughly. Repeat color combination in second pan. Remove, rinse and dry dividing ring.
Prepare third pan with dividing ring. Starting in center, fill center ring ½ full with dark green batter, next ring ½ full with medium green batter and outer ring ½ full with dark green batter. Remove dividing ring.
Bake and cool cakes.