Preheat your oven to 350°F (175°C). In a large bowl, combine the cake mix, water, eggs, and oil. Beat for about 2 minutes until the batter is smooth. Pour into a greased 9×13-inch pan and bake for 28–30 minutes, or until a toothpick comes out clean.

Let the cake cool for 15–20 minutes. Then, using the handle of a wooden spoon or a large skewer, poke holes all over the top. Go deep enough so the jello seeps in, but not all the way through the bottom.

In a small bowl, mix the boiling water with the strawberry Jello powder. Stir until completely dissolved. Add the cold water and stir again.

Slowly pour the jello over the cake, letting it fill the holes. Cover the cake and refrigerate for at least 2 hours (overnight is even better).

Spread the whipped topping evenly over the chilled cake. Use blueberries to create the stars part of the flag in the upper left corner. Line up strawberry slices for the red stripes across the rest of the cake.

Tip: Start decorating from the top left and work your way out — it’s easier to space everything evenly this way!