In a large bowl, stir together 2 cups all-purpose flour, sugar, salt and cinnamon. Using a pastry blender, cut in the shortening until pieces are pea-size. In a small bowl, combine cold water and 1/4 cup flour; stir until mixture is smooth. Pour water-flour mixture over the flour-sugar mixture; mix with a fork until all of the flour-sugar mixture is moistened. Gather mixture into a ball, kneading gently until it holds together.