Makes 4 dozen
Mix butter and sugar until creamy. Add salt, rum, flour and nuts. Mix well. Chill dough until easy to handle (anywhere from 1 hour to overnight).
Shape dough into 1-inch balls and place on ungreased cookie sheets.
Bake 12 to 15 minutes in a preheated 350° oven, or until golden brown. While cookies are still warm, roll in sugar. Will keep well if stored in airtight container.