Preheat oven to 350. In a large saucepan combine berries, sugar and cinnamon. Cook and stir until mixture comes to a boil. Combine the cornstarch and water in a jar and shake until smooth; add to berries. Bring to a boil; cook and stir for 2 minutes or until thick. Pour into a buttered 8x8 dish. Dot with butter.

To make topping, combine flour, sugar, baking powder and salt. Cut in butter with a pastry cutter or 2 knives, resembling coarse crumbs. Stir in milk just until flour is incorporated. Drop by tablespoons onto hot berry mixture.

Bake uncovered for 30-35 minutes. Serve warm with whipped cream or ice cream.