Cream sugar and butter. Add egg yolk (save white). Add vanilla. Add flour. Blend well (low speed on miser or work with hands).
Pick up little balls about the size of small walnuts. Roll in hands. Place on ungreased cookie sheets. Take bottom of flass and dip in egg white (lightly beaten) only once - just bottom of glass not too much egg white. Dip bottom of glass in sugar each time for each cookie - press or flatten them out. Decorations optional.
Dip glass in egg white (cleaned glass) for each try of cookies.

350 deggrees F for 8-10 minutes or until edges are slighly brown. Makes about 40 cookies