Heat oven to 350 degrees. Mix brown sugar, shortening, margarine, egg yolk, and vanilla. Mix in flour and salt untl dough holds together. Shape dough into 3 cm balls. Beat egg whites lightly. Dip each ball into egg white; roll in nuts. Place about 3 cm apart on ungreased cookie sheet. Press thumb deeply in center of each. Bake until light brown, about 8 to 9 minutes. Immediately remove from cookie sheet. Place a Hershey Kiss in the center of each cookie. Kiss will melt slightly from warmth of cookie. Let them cool thoroughly and the Kiss harden again before storing. Makes about 3 dozen cookies. If you prefer, you can make peanut butter cookies instead with the thumbprint and Hershey Kiss. Lilli Beach ----