Wash the duck legs, pat dry, parry excess fat and season with salt and pepper on both sides. Drain the fat in a small pan and briefly fry the legs one after the other on both sides. Peel the apple and cut into small pieces.
Put the duck legs, the chopped apple, juniper berries and allspice in a flat baking dish, pour in the stock and cook in the oven for approx. 90 minutes.
For the sauce, take the legs out of the stock and put them back in the oven on a plate.
Put the stock in a pan or saucepan. Remove the juniper, allspice and bay leaf and reduce to full speed for about 10 minutes. Then use the hand blender to puree the apple in the sauce, bind the whole thing with a little cornstarch and bring to the boil again. Season with salt and pepper and serve with the legs.