Hot Milk Sponge Cake

4 eggs, beaten
2 cups granulated sugar
1 1/4 cups milk
10 tablespoons butter
1 teaspoon vanilla extract
2 1/4 cups all-purpose flour
2 teaspoons baking powder

Heat milk with butter until hot but not boiling. Mix all ingredients together and pour into a 9 x 13-inch baking pan. Bake at 350 degrees F for 30-35 minutes.