For the glaze: Place all glaze ingredients in a heavy-bottomed pot and bring to a boil. Boil until the mixture is reduced by about one quarter (turn the heat to medium if you're nervous about burning). Remove from heat and set aside.
Preheat oven to 425F. Stuff the cavity of the duck with oranges and onions. Mix together oil, salt and pepper and rub over entire duck. Place duck on a rack in a roasting pan and put it in the oven for 10 minutes. Remove from oven and brush all over with glaze. Return to the oven for another 15 minutes. Reduce the heat to 375F and repeat the glazing process every 15 minutes until the glaze is gone, the duck is nice and crisp, and the internal temperature of the breast reaches 160F. Remove from the oven and allow the duck to rest for 10 minutes before cutting. Yield: 4-6 servings