Combine first 6 ingredients in a bowl, and stir well. Set aside. Place brown sugar, margarine, molasses, and egg white in a food processor, and process until blended. Add dry ingredients to food processor, and process until blended, scraping sides of processor bowl once. Gently press mixture into a ball; wrap in plastic wrap. Chill 2 hours.
Preheat oven to 375°.
Shape dough into 40 (3/4-inch) balls. Place granulated sugar in a bowl. Dip balls in cold water; shake to remove excess moisture. Roll wet balls in sugar. Place 3 inches apart on a baking sheet. Bake at 375° for 10 minutes. Remove from pan; let cool on a wire rack.