Step 1

Preheat your oven to 350 degrees. Spray a 13"x9" pan with cooking spray. Set aside.

Step 2

Follow the cake mix box directions to prepare the cake batter using the cake mix, 1 cup water, oil and the egg whites. Spread evenly into the prepared pan. Bake for 23 to 28 minutes, or until a toothpick inserted in the center comes out clean.

Step 3

Allow the cake to cool for 15 minutes in the pan. Then poke holes in the cake at ½-inch intervals.

Step 4

In a small bowl, add 1 cup of boiling water to the black cherry gelatin mix. Stir well, then add in ½ cup of cold water and stir again. Pour over the cake, making sure to get the gelatin into each of the holes. Refrigerate for at least 2 hours.

Step 5

Once the cake has chilled for at least 2 hours, spread the entire tub of whipped topping evenly over top of it. Use the blueberries and raspberries to create an American flag design on top of the whipped topping if desired.

Step 6

Serve immediately or refrigerate until ready to serve. Enjoy!