01 -
Heat your oven to 350 degrees and grease a 9x13 inch baking dish.
02 -
Prepare the white cake mix according to the package directions - usually it's the cake mix combined with water, oil, and egg whites. Mix everything together until smooth.
03 -
Pour the batter into your greased baking dish and bake for 29 to 33 minutes, or whatever time is listed on your cake mix box. The cake is done when a toothpick inserted in the center comes out clean.
04 -
Take the cake out of the oven and let it cool completely - this takes at least 20 to 30 minutes. Don't skip this step or the Jell-O will just melt into warm cake.
05 -
Use a fork to poke holes all over the cake in 5 columns going down the length of the pan. Make them deep but not all the way through to the bottom.
06 -
Put each Jell-O flavor in a separate bowl. Add half of the boiling water (about 1/2 cup) to each bowl and stir until the powder dissolves. Then add half of the cold water (about 1/2 cup) to each bowl and stir again.
07 -
Using a spoon, carefully pour the cherry Jell-O and lime Jell-O over the cake in an alternating pattern - some cherry, some lime, some cherry, creating stripes. The Jell-O will soak into the holes.
08 -
Put the cake in the fridge and chill for at least 1 hour to let the Jell-O set inside the cake.
09 -
Take the cake out of the fridge and spread the Cool Whip evenly over the top, covering the whole surface.
10 -
Sprinkle the Christmas sprinkles all over the Cool Whip. Put the cake back in the fridge and chill for at least another hour, but overnight is even better. This lets everything set perfectly. Slice and serve cold!