Preheat the oven to 350°F (175°C). Grease and flour a cake pan.

In a large bowl, whisk together the flour, sugar, baking powder, and salt.

Add the milk, melted butter, eggs, and vanilla extract to the dry ingredients and mix until well combined.

Pour the batter into the prepared cake pan and smooth the top.

Bake for 25 minutes or until a toothpick inserted into the center comes out clean. Allow to cool.

In a separate bowl, whip the heavy cream with powdered sugar and vanilla extract until soft peaks form.

Once the cake has cooled, spread the whipped cream on top.

Decorate with blueberries, sliced strawberries, and raspberries to resemble the American flag.