1Toss blueberries with cinnamon and lemon juice. Put in greased 8 inch square baking dish. In a bowl, combine flour, sugar and baking powder; stir in milk and butter. Spoon over berries. Combine sugar and cornstarch from the topping ingredients; sprinkle over batter. Slowly pour boiling water over all.
2Bake at 350* for 45-50 mins or till the cake tests done.