Prepare the Cookie Base: Preheat your oven to 350°F (175°C). Roll out store-bought dough or prepare homemade sugar cookie dough into a large circle on a baking sheet lined with parchment paper.
Bake the Cookie: Bake for about 15–20 minutes or until the edges are golden brown. Allow to cool completely.
Frost the Cookie Base: Spread a generous layer of cream cheese frosting evenly over the cooled cookie base.
Decorate with Fruit: Arrange blueberries in the upper left quarter for stars and layer sliced strawberries across the remainder to represent stripes.
Add Final Touches: Sprinkle mini marshmallows or colorful sprinkles on top and add food coloring gel if desired.
