Cream sugar, butter and egg until well blended. Add lemon juice and peel. Combine flour, baking soda, cream of tartar and salt. Stir into creamed mixture. Cover and refrigerate the dough for at least 1hour.
Roll into 1-inch balls. Place on ungreased baking sheet. Bake at 350 degrees for 9 minutes or until bottoms are lightly browned. Remove to wire rack and cool for 5 minutes. Roll in powdered sugar. Makes about 2 dozen.