Leave the duck for 1-2 hours at room temperature. If using frozen duck, defrost in the refrigerator for at least 12 hours. Remove the giblets pouch from inside the duck, cut off the last 2 wings and pull the fat from the inner cavity.
Boil 3-4 liters of water in a large pot. Dip the duck in the boiling water for 30 seconds. Take out, drain and pat dry with a paper towel. With a sharp knife or toothpick, prick the skin of the duck, especially the breast.
Put all the spices and salt in a mortar and grind well. Put in a bowl, add the sugar and mix. Rub the ground spices on the duck, salt the duck inner cavity and return to the refrigerator for 1 hour so that the skin can dry.
Take the duck, put the sliced orange inside and pinch the hole with a toothpick or small skewer. Roast the duck in a baking tray with a rack for 1 hour in a preheated oven at 180°C. Take out of the oven, remove the rack and pour off the fat that has been released during roasting.
Place the powdered sugar and the thawed cherries in a baking pan. Pour in the vodka, soy sauce, add ginger and cinnamon, the thin slices of orange peel and mix well. Return the duck to the pan and bake for another 60-70 minutes, until the sauce is reduced and the duck is well cooked.
Boil the peeled and coarsely chopped potatoes for 5 minutes in salted water. Drain and let them dry for another 5 minutes. Arrange in a baking pan, add 3-4 tbsp duck fat, mix and bake for 45-50 minutes in a preheated oven at 230°C. Turn the potatoes halfway through to brown on all sides.