Preheat oven to 350. In a medium-size bowl, combine 3/4 cup of the sugar, flour, three tablespoons of the cocoa, baking powder and salt. Blend in milk, melted butter and vanilla; beat until smooth. Spread into an 8 inch square pan. In a small bowl, combine remaining 1/2 cup sugar, brown sugar and remaining 1/4 cup cocoa; sprinkle mixture evenly over batter. Combine hot water and kirsch; pour over batter. Do not stir. Bake for 40 minutes, or until center is almost set. Let stand 15 minutes. Transfer to dessert dishes and spoon pudding from bottom of pan over cake. Serve with cherry pie filling as sauce. (great without the cherry pie filling, and/or with whipped cream.)