Bake cake. Prepare cake batter following recipe instructions. Bake and cool two cake layers. Trim both layers to 2½ in. high. Fill and stack layers for 5 in. high cake.

Ice cake smooth. Let icing fully crust, about 1 hour.

Tint icing. Tint 1/3 cup icing each light blue and light green using color combinations provided. Combine Royal Blue and Violet icing colors to get light blue color shown. Combine Lemon Yellow and Leaf Green icing colors to get light green color shown. Using Royal Blue, Ivory and Teal icing colors, tint 1/3 cup icing each blue, ivory and teal. Reserve remaining icing white.

Make template. Print out 7 template. Using FoodWriter marker, trace template on parchment paper. Cut out 7 from parchment paper.

Wipe solid vegetable shortening on back of 7 template. Stick to side of cake.

Decorate cake. Using spatula, swipe light blue, light green, blue, ivory and teal icing randomly around cake. Carefully remove 7 template.

Prepare decorating bag with tip 1M and remaining white icing. Pipe stars on top of cake.