Polish Teacakes
["1/2 c. butter", "1 egg yolk, slightly beaten", "1/2 tsp. salt", "1/2 c. sugar", "1 c. flour", "1/2 tsp. vanilla"]
["Cream butter and sugar until light.", "Add egg yolk; mix well. Add flour and salt; mix.", "Roll dough in small balls; dip in unbeaten egg white.", "Roll in finely chopped nuts.", "Place on buttered baking sheet; press down center of each with thimble. Bake in a 325\u00b0 oven for 5 minutes.", "Remove; press down again with thimble.", "Return to oven for about 10 to 15 minutes.", "Remove from oven; fill indents with preserves while hot."]
["butter", "egg yolk", "salt", "sugar", "flour", "vanilla"]