Today is my son Kellan's 19th birthday, When I asked him what kind of cake he wanted he said "surprise me" .... That is exactly what I did. This fabulous cake was found at the idea room . Kellan thought it was the coolest thing ever. It tasted great.
I took two white cake mixes and mixed them up in a large bowl according to the directions on the box. Then I divided the batter into 6 different bowls. Each bowl ended up with about 1 and 3/4 cups of batter each. Then I mixed some food coloring into each bowl to get my rainbow colors. I used the gel food colors rather than the liquid drops. Bake each layer at 350* for approx 12 minutes.
After all the cake layers have cooled, place your bottom layer (purple) onto your cake plate. Add a thin layer of frosting. Place your blue cake layer on top of the frosting. Continue in this manner until you have added all your cake layers.The frosting recipe used for this cake is as follows:(*I added cream cheese to original recipe in place of 1/2 the butter)
Place 1sticks of salted butter, and 8oz of cream cheese at room temperature (otherwise you will get chunks of butter in your frosting), into mixer and whip together until nice and smooth. Then add 1 tsp of vanilla. Gradually add about ¾ of a bag (regular size about 6 cups? ) of powdered sugar (Confectioner’s sugar). It will be a bit chunky and not very smooth. Gradually add 1 tsp. of milk while mixing frosting. If it is still not the consistency you desire, add another tsp of milk until you get a nice thick frosting that is smooth. Then fold in 1 tub of Cool Whip. That’s it. This makes a very light and creamy frosting. This is just enough for frosting this BIG cake. Make sure to go easy on the frosting between layers so you have enough to cover the entire cake.