In a large bowl, sift flour, powdered sugar and salt. Add shortening, vanilla and citrus peel and mix at low speed until blended.
Roll dough into 2 inch cylinders and chill for an hour or more.
Preheat oven to 350℉. Slice dough in ¼ - ½" slices and place on parchment paper lined cookie sheets. Bake for approximately 10 minutes, until the dough just sets, but cookies have not yet started to turn brown.
Remove from cookie sheets and cool on racks.
Melt chocolate dipping wafers as per package directions and dip one end of each cookie. Place on parchment paper until set.