Place the duck breast side up and using a sharp knife, score parallel slits 3/4-inch apart across the breast. Repeat scoring the opposite direction to make a crosshatch pattern. Be careful not to cut into the breast meat. Flip the bird over and cut parallel lines across the bottom as well. Using the tip of the knife, prick the skin all over, again, not cutting into the meat itself. This will allow fat to drip out of the skin, producing a crispy bird. Rub inside and out generously with salt and refrigerate uncovered overnight to allow the salt to season the bird and the skin to dry out (this also promotes a crispy skin).

Preheat the oven to 300ºF.

Place the duck in the sink and fill the largest pot you have with water and bring it to a boil. Pour boiling water over the duck. This helps begin melting the fat under the skin and also promotes a crisp skin.

Tear a large piece of foil and gently crumple it so that it fits into the bottom of a dutch oven and keeps the duck slightly elevated off the bottom of the pan. Place the duck in dutch oven on top of foil. Roast, uncovered for 2 1/2-3 hours at 300ºF, or until the thickest part of the leg is 165ºF then remove from oven to rest for 30 minutes.

While duck rests, make the glaze. Combine ingredients in a small pan and bring to a simmer and cook until reduced to a couple of tablespoons and the mixture is slightly thickened.

Turn oven to 450ºF and return the roast duck for 5 minutes. Remove from the oven, use a spoon to spread the glaze all over the bird and roast for another 5-8 minutes. Rest 10 minutes before serving.