8
Start at one end of cake and pour a spoonful of purple ganache over the top edge allowing it to drip down the sides of the cake. Next to the purple add a spoonful of blue, then green, yellow, orange, red, then pink, repeating this as you go around the entire cake. If desired, swirl the colors on the top of the cake. If the ganache becomes too thick, heat it in the microwave for about 10 seconds to thin it out.