Martha Stewart's blueberry crisp recipe is a good recipe that comes from a June 2009 issue of Martha Stewart Living. The recipe makes eight servings.
To prepare the blueberry crisp, preheat the oven to 375 F. In a large bowl, mix 3 pints or 6 cups of fresh blueberries, 1 tablespoon cornstarch, 1 teaspoon fresh lemon juice, 1/4 cup sugar and 1/4 teaspoon coarse salt. Pour the filling mixture into a square, 8-inch baking dish, and set aside. In a separate mixing bowl, mix 3/4 cup all-purpose flour, 1/2 cup rolled oats, 1/2 teaspoon baking powder and another 1/2 teaspoon coarse salt. Cream together 6 tablespoons softened unsalted butter and 1/3 cup sugar, and add it to the dry mixture. Use your hands to thoroughly blend the crumb topping.
Sprinkle the topping evenly over the blueberry mixture, and bake the dish for about an hour or until the center is bubbling and the topping is browned. Place the dish on a wire rack to cool for 30 minutes. Cut it into squares and serve with a dollop of whipped cream or vanilla ice cream. Feel free to substitute chopped nuts for the rolled oats, or add an extra teaspoon of cornstarch to the filling for a thicker blueberry crisp. Also consider freezing extra batches of the topping for future fruit crisps.