Combine first 4 ingredients in a bowl; set aside. Beat margarine at medium speed of a mixer until light and fluffy. Gradually add granulated sugar, beating at medium speed of a mixer until well-blended.
Add vanilla and egg white, and beat well.
Add flour mixture, and stir until well-blended. Turn dough out onto wax paper; shape into a 6-inch log. Wrap log in wax paper; freeze 3 hours or until very firm.
Preheat oven to 35
Roll log in turbinado sugar.
Cut log into 24 (1/4-inch) slices; place 1 inch apart on a baking sheet coated with cooking spray.
Bake at 350 for 8 to 10 minutes.
Remove from pan; cool on wire racks.
Chocolate-Peppermint Variation: Substitute 1 teaspoon of peppermint extract for the vanilla extract.