In a saucepan, combine water, white sugar, salt, cornstarch and food coloring (optional). Bring to a boil, and cook for about 5 minutes or until thickened. Set aside to cool. Preheat oven to 350 degrees F (175 degrees C.)
In a large bowl, combine flour, confectioners' sugar, and vanilla. Cut in butter until the mixture resembles small crumbs. Press into a 9-inch pie pan. Prick all over with a fork and bake in the preheated oven for 8 to 10 minutes, or until lightly browned.
When crust is cool, place berries in the shell, and pour the thickened mixture over the top. Chill in refrigerator.
