Upside Down Blackberry Cake

1/4 cup brown sugar
2 tablespoons butter
2 cups blackberries
1/2 cup margarine or butter
1 3/4 cups sugar
2 eggs
1 1/2 cups flour
2 teaspoons baking powder
3/4 cup milk
1/2 teaspoon salt
1 teaspoon vanilla

Preheat oven to 350° F.

Heat brown sugar and 2 tablespoons butter in an 8- or 9-inch round pan or iron skillet over medium heat. Add berries and cook, stirring until mixture bubbles. Add 3/4 cup of the sugar and crush berries slightly. Cook for five minutes, and then remove from heat and set aside.

Mix 1/2 cup butter and remaining sugar (1 cup) until light. Blend in eggs. Mix flour, baking powder and salt together and add alternately with milk to creamed butter/sugar mixture. Add vanilla. Pour batter over cooked fruit in pan and bake for 35 to 40 minutes. Let stand in pan until lukewarm, then run knife around edge of pan and turn onto a large plate. Don't let it get too cool or it will stick and not come out of the pan. Top with sweetened whipped cream.