Preheat oven to 350˚F (175˚C).
Cream the butter with 1/2 cup of the confectioners' sugar and the vanilla. Mix in the flour, nuts and salt.
Roll about 1 tablespoon or so of dough into balls and place on an un-greased cookie sheet.
Bake at 350˚F for 15 minutes. Do not allow these cookies to get too brown. It's better to undercook them than to overcook them.
While cookies are still hot roll them in confectioners' sugar.

Once they have cooled roll them in confectioners' sugar once more.