Clean the duck(鸭子yāzǐ). Wipe dry and tie string around neck. Hang duck in cool, windy place four hours. Fill large wok with water. Bring to boil. Add ginger, scallion(青葱qīngcōng), honey, vinegar, and sherry. Bring to boil. Pour in dissolved cornstarch(starch prepared from the grains of corn; used in cooking as a thickener). Stir constantly.

Place duck in large strainer above larger bowl. Scoop boiling mixture all over duck for about 10 minutes. Hang duck again in cool, windy place for 6 hours until thoroughly dry. Place duck breast side up on a greased rack in oven preheated to 350 degrees. Set a pan filled with 2 inches of water in bottom of oven. Roast 30 minutes.

Turn duck and roast 30 minutes more. Turn breast side up again. Roast 10 minutes more. Use sharp knife to cut off crispy skin. Serve meat and skin immediately on a prewarmed dish. The duck is eaten hot with hoisin sauce rolled in Mandarin Crepes. Garnish with scallion flowerets. Serves 4 to 6.