Fourth of July Flag Slab Pie

Name: Fourth of July Flag Slab Pie
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Cuisine: American
Ingredients: 1 batch All-Butter Pie Crust,; Coarse sparkling sugar; 1 pint (480 ml) blueberries; 2 tablespoons sugar; 1 tablespoon cornstarch; 1 teaspoon water; 1 teaspoon lemon juice; 2 quarts (2 L) fresh strawberries, (hulled and chopped); 1/2 cup (99 g) sugar; 2 tablespoons cornstarch; 2 tablespoons water; 1 tablespoon lemon juice