For the sauce:
2 cups duck stock; prepare ahead of time, as it must simmer for two hours. To blanche orange peel, take 4 oranges and remove the orange part of the skin in strips with a vegetable peeler. Simmer for 15 minutes in a quart of water. Drain and pat the peels dry with paper towels.
Use a duck that is about 5 1/2 lbs. Place in a roasting pan and season the duck with 1/2 tsp. salt and a pinch of black pepper. Add a third of the prepared orange peel. Truss the duck. Roast at 425 degrees Fahrenheit for an hour and a half to two hours. Every now and then, baste with juices. The meat is done when a thermometer measures 165 degrees F.