Preheat oven to 350 degrees and spray a 9x13 baking dish.
In a small bowl, mix until combined the hot water and jello. Allow to cool to room temperature.
Using a standing mixer, beat until combined the cake mix, 1/4 C jello, 1/4 C lemonade concentrate, water, oil and egg whites.
Pour batter into the baking dish and bake for 35-40 minutes or until a toothpick comes out clean.
Using the bottom of a wooden spoon or bamboo skewer, poke holes all over the cake.
Pour 3 tbsp of the jello into a squeeze bottle and set aside.
In a small bowl, whisk together 1 tbsp of the jello and 1/4 C of lemonade concentrate.
Pour the mixture over the cake, make sure the mixture gets into the holes.
Allow to cool for 2 hours in the fridge.
In a large bowl, fold together the frosting and cool whip.
Frost over cake.
Using the squeeze bottle, pipe lines of the jello across the cake.
Using a butter knife, pull the knife through the lines to create zig-zags.