Cream butter and sugar. Add yolk and flour. Cut in fruit and nuts. Shape dough into two rolls 2 inches in diameter and roll in waxed paper. Chill overnight.
Preheat oven to 375 degrees F (190 degrees C).
While still cold and wax paper still on, take a sharp knife and cut thin slices (1/8 inch). Set on greased cookie sheets, remove wax paper and bake for 10 minutes. (Slightly brown edges).
