Bake cake and allow it to cool completely.
While the cake is baking and cooling, prepare frosting.
Divide frosting in separate bowls and tint them red, yellow, orange and black, using gel colors.
Place cake on serving dish.
Ice the cake completely in red frosting.
Use a toothpick to make an eyeball outline in the center.
Fill a piping bag with red icing and cut out a small opening with scissors.
Pipe in a zig-zag motion around the outline.
Fill another piping bag with orange icing and pipe roughly around the red icing.
Fill another piping bag with yellow icing and pipe roughly around the orange icing.
Fill another piping bag with black icing and fill the center.
Use a paintbrush to blend all the colors roughly, leaving out the black center. Don't blend the center.
Also, brush some black icing randomly on top of the cake.
For the side of the cake, brush red, yellow, orange and black icing randomly. Enjoy!