fresh or frozen blackberries
Preheat the oven to 400 degrees F.
For the Filling
Combine the sugar and cornstarch in a saucepan, and add the water.
Add the blackberries, and cook on low to medium heat until thick and bubbly, stirring constantly.
Keep warm while preparing the topping.
For the Topping
Mix the dry ingredients (flour, sugar, baking powder, and cinnamon) in a bowl and add in the butter with a fork until it forms coarse crumbles.
Combine the egg and milk in a separate bowl, and then add to the flour mixture, stirring to just combine and moisten.
For the Cobbler
Pour the filling into a greased 8" x 8" baking dish, and drop the topping in mounds on top of the hot filling.
Bake at 400 F for 20 - 25 minutes, or until the topping is golden brown and a toothpick inserted in the middle comes out clean.
Serve warm, and top with ice-cream (optional).