Blueberry Cornbread    1-2 tablespoons Vegetable oil  1 ½ cups blueberries  1 cup + 1 teaspoon all-purpose flour, divided  1 cup yellow cornmeal  1/3 cup light brown sugar  1 tablespoon baking powder  ½ teaspoon salt  1 large egg, lightly beaten  2/3 cup milk  ½ cup Vegetable oil  ½ teaspoon vanilla extract