Creamy Patriotic Cake for 20 Servings

Instructions:

1. Preheat oven to 350°F (175°C). Grease a 9x13 inch baking pan and line it with parchment paper.
2. Cream the softened butter and granulated sugar together until pale and fluffy. Incorporate eggs one at a time, then stir in the vanilla extract.
3. Alternately add the flour, baking powder, and salt mixture and the whole milk to the batter, mixing until just combined.
4. Pour the batter into the prepared pan and bake for 30 minutes or until a toothpick inserted into the center comes out clean. Let the cake cool completely on a wire rack.
5. In a chilled bowl, beat the chilled cream cheese and softened butter until smooth. Gradually mix in powdered sugar and vanilla extract.
6. Pour in the heavy cream and whip on high for 2 minutes until the frosting is stiff and glossy. Spread an even layer across the cooled cake.
7. Toss strawberries and blueberries in lemon juice, then pat them dry with a paper towel.
8. Arrange blueberries in a tight rectangle in the top-left corner. Create alternating horizontal stripes of sliced strawberries and white frosting across the remainder of the cake, pressing fruit gently into the cream.
9. Chill the cake for 2 hours before serving to ensure stability.