Blueberry Upside-Down Cake recipe.

Ingredients
6 tablespoons softened butter, divided
1/4 cup packed brown sugar
2 cups fresh blueberries
3/4 cup sugar
1 teaspoon vanilla extract
1 1/4 cups cake flour
1 1/2 teaspoons baking powder
1/2 cup milk
whipped topping

Directions
In a small saucepan, melt 2 tablespoons butter; stir in brown sugar. Spread into an ungreased 8-in. baking dish. Arrange blueberries in a single layer over brown sugar mixture; set aside. In a large mixing bowl, cream remaining butter; beat in sugar. Add egg and vanilla; mix well. Combine flour and baking powder; add to creamed mixture alternately with milk. Carefully pour over blueberries.
Bake at 350 degrees F for 40-45 minutes or until a toothpick inserted near the center of cake comes out clean. Immediately invert onto a serving platter. Cool. Serve with whipped topping if desired.