Bring 3 cups blueberries to a boil with 1/3 cup sugar and 1 tablespoon cornstarch or arrowroot. Simmer 3-5 minutes; remove from heat and set aside. Taste the fruit and adjust sugar to your taste; some blueberries are extra tart and require additional sweetening.
Preheat oven to 425°F.
Whisk together flour, salt, sugar and baking powder.
Cut in butter using a pastry cutter or a wide fork. Lightly stir in milk just until combined.
Turn dough out onto a lightly floured board and gently knead for 30 seconds. Divide into 2 portions.
Pat 1/2 of the dough into a buttered 8x8 inch pan. Cover with half of the hot fruit, to the edges. Dot with 2 tablespoons butter over top. Bake for 30 minutes and serve with vanilla ice cream and blueberry sauce.
Alternatively, the fruit may be layered on the bottom and covered with the dough, and buttered on top.
Makes 2. The second may be covered well and frozen for up to 3 months.
