2 large tart apples *granny smith or honey crisp- cored peeled, and roughly chopped into small pieces 1 1/2 tsp cinnamon + a little extra for topping 2 tsp pure vanilla or vanilla extract 1/4 cup brown sugar + 2 tbs for the topping 1/4 cup nonfat sour cream 1/2 cup water 1 tbs butter , melted, for topping pinch