Heat brown sugar and butter in nonstick, ovenproof 10-inch skillet to melt sugar. Add apple. Cook, stirring occasionally, 10 minutes until lightly browned. Cook 5 minutes more, while carefully arranging apple slices in concentric circles, using small tongs.
Whisk together the cornmeal, granulated sugar, flour, baking powder, baking soda and ginger in a large bowl.
Whisk together the buttermilk, molasses, egg and oil in a small bowl. Whisk the buttermilk mixture into the cornmeal mixture until well blended. Spoon the batter over the apples, spreading out evenly with the back of a spoon. Batter will spread more as it bakes.
Bake in preheated 400°F oven for 15 to 20 minutes or until cake springs back when lightly touched in center. Invert cake onto heatproof serving plate. Serve warm.