In a bowl, beat together the butter and the powdered sugar until smooth and creamy. Add vanilla. Blend together flour, salt and just the Dash of baking powder. Add flourmix to buttermix, blend well. Add the chopped nuts, combine well. Roll the dough out into two balls.Wrap in platic wrap and chill for at least 1 hour. Flatten dough out and cut into 15-16 equal sized pieces. Shape into marble sized balls. Place on ungreased cookiesheets. Bake at 375-400 degrees F for 10-12 minutes each sheet until firm but Not brown. While still warm roll into powdered sugar. Let cool and roll in sugar again. They store well and are very yummy!!!