If you are in the market for an impressive make-ahead summer dessert, this Rainbow Sherbet Roll is one delicious dessert. Make a day ahead of time, then slice and serve as needed.
Preheat oven to 350ºF. Line 15 1/2x10 1/2x1-inch jelly roll pan with waxed or parchment paper. Beat cake mix and cold water in extra-large glass or metal bowl on low speed 30 seconds; beat on medium speed 1 minute. Spread half of the batter in pan. (You can make cupcakes or a loaf cake with the remaining batter.)