Preheat oven to 475 degrees and boil 2 cups water.
Prepare a roasting pan or broiler pan an elevated grate.
Place duck(s) on the broiler pan, pierce skin several times. This will allow the fats and steam to release from the duck, helping the skin crisp up.
Pour boiling water over duck, the skin will tighten. Allow to cool and dry. Leave remaining water in the bottom of the roasting pan.
Mix Kosher salt through marjoram in a small bowl. When duck is cooled and dry, generously rub skin with spice mixture, any remaining can be rubbed on the inside cavity. Stuff inside cavity with cubed orange and truss duck just like a turkey.
Add orange juice and white wine into the bottom of the roasting pan.
Place duck into the oven at 475 degrees for 10 minutes to create the crust, then lower temperature to 350 degrees.
Roast for approximately 1 hour and 15 minutes, or until thermometer registers to 170 degrees in the thigh. While duck roasts, start to assemble your orange sauce (see below).
To finish, turn broiler on high, watching closely, for an additional 3-4 minutes to evenly brown the top of the duck.
Remove, transfer to a cutting board and allow to cool while you finish off your a'l orange sauce.
Pour liquid in the bottom of the roasting pan into a gravy separator. Skim off all fat* and measure out 1 cup drippings for the sauce.
A l'Orange Sauce:
Place sugar in a dry saucepan over medium heat. Swirl every so often until sugar dissolves. It will start to melt and caramelize to an amber color.
Immediately whisk in orange juice and white wine vinegar. Mixture will spit and sizzle, sugar will harden, but have no fear, keep stirring and it will dissolve. Set aside.
In a separate small bowl, mash together room temperature butter with flour and set side.
Whisk 1 cup duck drippings mixture with salt and butter-flour to make a thick paste. Stir in orange marmalade.
Caramelized mixture should still be fairly warm, whisk with duck dripping-orange marmalade to make one sauce.
Baste sauce all over duck right before serving. This keeps the skin crispy, but covers it with flavorful sauce.
If you've tried this recipe, come back and let us know how it was!
Notes
Reserve fat and roast with vegetables or potatoes.