Combine flour, sugar, baking powder and salt in bowl. Stir in milk. Spread batter in a 9 inch greased baking pan or dish. Combine pure Vermont maple syrup, water and butter in saucepan and heat until butter is melted. Pour this over the batter in the pan and bake about 45 minutes in a 350 degree oven until cake is lightly browned. The maple syrup mixture will sink to the bottom where it forms a pudding-like sauce. Whipped cream or ice cream may be added.