01 -
Preheat oven to 350°F. Spray a 9x13 glass baking dish with nonstick baking spray and set aside.
02 -
Beat together cake mix, eggs (or just egg whites if using), oil, and 1 cup of milk until fully combined.
03 -
Divide the cake batter evenly into three bowls. Tint each bowl of cake batter, adding just a drop or two of food coloring at a time and then adding more to control the color of the cake batter.
04 -
Drop large spoonfuls of the cake batter throughout the prepared baking dish, rotating the colors. (TIP - Using an ice cream scoop or large cookie dough scoop makes it easy to dispense the batter.) Use a knife to swirl the colors slightly - do not over swirl or the colors will become muddy and mixed.
05 -
Bake the cake for 25-30 minutes, until the center is set and a toothpick comes out with just a few crumbs when poked in the center of the cake. Allow the cake to cool.
06 -
When the cake has cooled most of the way, use the round handle of a wooden spoon or a wooden dowel to poke holes all over the cake. Poke the holes about 2⁄3 of the way down into the cake, spacing 3⁄4"-1" apart.
07 -
Prepare the pudding mixture. Whisk together the instant pudding mix with the remaining 2 cups of milk. Whisk for 1-2 minutes until the mixture is fully combined and just beginning to thicken. Pour the pudding mixture over the cake and spread over the top, pressing the pudding down slightly while spreading so that it fills the holes.
08 -
Place the cake in the refrigerator for 30 minutes to allow the pudding to thicken. Top the cake with Cool Whip and decorate with sprinkles or however you wish.