Preparation time: 1 hr
Cooking time: 60-70 min
Trim duck wings and feet. Hang duck in a well-ventilated room temperature place for four hours. Combine the broth ingredients in pot and bring to a boil. Blanch whole duck in broth by hanging over boiling liquid and scoop broth over duck. Let duck hang again for six hours until skin is completely dry and soft to the touch.
Stuff duck with ginger coins, mango, salt and black pepper. Skewer duck closed.
Place ducks on a rack directly on the oven shelf. Place a pan with water at the bottom of the oven to catch the drippings. Roast duck in 300º F oven. 30 minutes breast side up. 30 minutes breast side down. 10 minutes breast side up.