Rainbow Cake

2 boxes white cake mix

24 oz of clear diet soda (2 cans, ginger ale and sprite work well)

gel food colouring

16 oz whipped topping

2 oz instant fat-free sugar-free pudding mix (2 smallish boxes)

Mix the cake mix with the soda according to regular instructions on box. It will be lumpy afterward. Again, you can use any white cake recipe you want, this is just how I do it.

Measure the total volume (by my estimate, 64 oz), then divide by 6 and measure into separate bowls. There are 8 oz in a cup, so 64/6 = 10 to 11 oz, or 1 cup + 2 tbsp. Stir colour into each bowl with its own spoon. For the first colour into the pan, measure out 2/3 to 3/4 of your mix (in this case about 1 c) as close to the middle as you can. Drop in your first three colours, then work on the other pan with the last three colours. So if you’re doing rainbow order, the first pan should have red, then orange, then yellow, and now the purple, blue and green go into the second pan. As a recap, this is so both layers are roughly the same size.

Bake the cake as instructed on the box. Check it when the box says to, but usually it’ll need an extra 5 or 10 minutes because of the density of the soda method. Just keep baking, checking back every 5 minutes or so until a toothpick to the center comes out clean. Let cool completely before moving to a wire rack.

Meanwhile, make your frosting. Just mix the pudding mix in with the whipped topping for a few minutes. Dye if you’re into that. Layer your cake and frost your fat-free cake with your fat-free whipped frosting. Eat.

For more pictures and more info: http://www.omnomicon.com/rainbowcake