1/2 c. butter
1/2 c. sugar
1 egg yolk, slightly beaten
Chopped walnuts
1 c. flour
1/2 tsp. salt
1/2 tsp. vanilla

Cream butter and sugar until light and fluffy. Add egg yolk and vanilla, mix well. Add flour sifted with salt. Mix. Roll dough in small balls; dip in unbeaten egg whites and roll in finely chopped nuts.

Place on greased cookie sheet and press down center of each with thimble. Bake at 325 degrees for 5 minutes. Remove from oven and press down again with thimble. Return to oven for about 10 to 15 minutes longer. Remove from oven and fill indentation with preserves while still warm.