Preheat oven to 350 degrees. Cut butter into flour till coarse. Add sugar, soda, cream of tartar, egg and enough hot water to make dough that can be rolled like pastry. Roll 1/8 to 1/4 inch thick on a board sprinkled with a little white flour. Cut into 3 inch squares. Place on an ungreased baking sheet. Bake 15 to 20 minutes. Cool on rack. Brush tops with butter.
Each serving: 105 calories; 1 g. dietary fiber; 14 g. carbohydrates; 1 g. protein; 5 g. fat; <1 g. saturated fat; 17 mg. cholesterol; 35 mg. sodium.