1/2 c. butter
1/4 c. brown sugar
1 egg, separated
1 c. flour
Vanilla
1 1/2 c. chopped walnuts

Cream butter and sugar; add egg yolk, flour, and vanilla. Form in small balls and dip in slightly beaten egg whites. Roll ball in nut mixture. Bake 5 minutes at 350 degrees. Remove from oven. QUICKLY press thumb gently on top of each cookie. In thumbprints, put a little candied fruit, jelly, jam, or sugar icing. Bake another 8 minutes at 375 degrees. Makes about 24 cookies.