Sprinkle these buttery cookies with confectioners' sugar while still warm. The heat from the cookies melts the sugar just a little allowing it to better coat the cookies.
Beat together butter and 1/2 cup confectioners' sugar in bowl until creamy. Add lemon juice and vanilla. On low speed, beat in flour, nuts, and zest (dough will be slightly stiff). Wrap in plastic and refrigerate 1 hour.
Heat oven to 325 degrees F. Pinch off heaping tablespoonfuls of dough. Roll into balls. Place 1 to 2 inches apart on ungreased baking sheets.
Bake cookies in 325 degree F oven for 16 to 18 minutes, or until slightly browned near the bottoms of the cookies. Remove cookies to wire rack.
Sift remaining 1/3 cup confectioners' sugar over still-warm cookies to coat. Resift once cooked, if desired. Makes 3-1/2 dozen cookies.