Mix flour, cocoa powder, baking soda and salt in medium bowl. Set aside. Beat butter and sugars in large bowl with electric mixer on medium speed until light and fluffy. Add egg and extracts; mix well. Gradually beat in flour mixture on low speed until well mixed. Divide dough in half. Roll each into a 12-inch log. Wrap in plastic wrap. Refrigerate 1 hour or until firm.
Preheat oven to 350°F. Roll each log in white sugar crystals to coat. Cut logs into 1/2-inch thick slices. Place on ungreased baking sheets.
Bake 10 to 12 minutes or until cookies are set. Cool on baking sheets 1 minute. Remove to wire racks; cool completely.