Mix arrowroot or cornstarch in cold water. Stir into 1-1/2 cups more cold water or orange juice. Pour over vegetables. Lower heat. Stir and simmer until slightly thickened. Pour all over crust. Sprinkle with 1/2 cup chopped nuts. Bake at 375 F. for 45 minutes or until set. Other vegetables may be substituted for those above, such as mushrooms, cauliflower, purple cabbage, celery, etc.