Truffle-Iced Sugar Cookies

Cookies:

• cup all-purpose flour
• 1/4 teaspoon baking soda
• 1/8 teaspoon salt
• 4 tablespoons butter, softened
• 2/3 cup granulated sugar
• 1 teaspoon vanilla extract
• 1 large egg white
• Cooking spray
  
  
  Icing:
  
  
• 1 cup powdered sugar
• 2 teaspoons unsweetened cocoa
• 1 tablespoon fat-free milk
• 1/2 ounce semisweet chocolate
• 1/2 ounce white chocolate

1. To prepare cookies, lightly spoon flour into a dry measuring cup; level with a knife.
2. Combine flour, baking soda, and salt in a bowl, stirring well with a whisk; set aside.
3. Beat butter with a mixer at medium speed until light and fluffy.
4. Gradually add granulated sugar, beating until well-blended.
5. Add vanilla and egg white; beat well. Add flour mixture; stir until well-blended.
6. Turn dough out onto wax paper; shape into a 6-inch log.
7. Wrap log in wax paper; freeze for 3 hours or until very firm.
8. Preheat oven to 350°F (177°C).
9. Cut log into 24 (1/4-inch) slices; place the slices 1 inch apart on a baking sheet coated with cooking spray. Bake at 350°F (177°C) for 8 to 10 minutes.
10. Remove the cookies from pan, and cool on wire racks.
11. To prepare the icing, combine powdered sugar and cocoa in a small bowl; stir well. Add milk; stir well.
12. Spread over cookies to within 1/4 inch of their edges.
13. Place semisweet and white chocolate in separate heavy-duty zip-top plastic bags; seal.
14. Microwave chocolates at high for 1 minute or until chocolates are soft.
15. Knead the bags until smooth. Snip a tiny hole in corner of bags; drizzle chocolates over the frosted cookies so that they resemble truffles.