Gluten Free Rhubarb Pie With Sorghum Crust Recipe

Name: Gluten-Free Rhubarb Pie With Sorghum Crust Recipe
Ingredients: For the Crust; 4 ounces (about 1 cup) sorghum flour; 1.25 ounces (about 1/4 cup) sweet rice flour; 1 ounce (about 1/4 cup) tapioca starch; 2 tablespoons granulated sugar; 3/4 teaspoon salt; 4 ounces (1 stick) butter, chilled and cut into six pieces; 1 large egg; 2 tablespoons cold water, divided; For the Filling; gluten-free cooking spray; 1/2 cup granulated sugar; 2 tablespoons cornstarch; 14 ounces (about three cups) sliced rhubarb; 1 tablespoon lemon juice (about one tablespoon)