Beat butter on medium speed in mixer bowl till soft. Add sugar and salt and beat till fluffy. Add egg, extract and a few drops of coloring, and beat well.
With mixer on low add flour. Beat well.
Divide dough into 3 equal parts. Shape into rolls about 1" thick and 8" long. Roll each in green sugar.
Wrap rolls in plastic wrap or foil and chill for at least 2 hours.
Slice into 1/4" thick rounds. Place 3 slices of dough, sides touching, on an ungreased cookie sheet. Cut a stem from a fourth slice and attach to the shamrock. (Save the rest of this slice for cutting other stems). With 3 fingers, gently push the slices together so each leaflet curves in slightly to form a shamrock.
Bake 350° about 8 minutes or till edges are light brown.
Recipe submitted by Dobie on 3/9/00