Preheat the oven to 250°C/500°F/Mark 10. Hold the duck in a gas jet to remove all the remaining stubs of feathers (or use a taper). Remove the feet, wing tips and neck with a large knife. If the duck has not yet been gutted, do so, leaving in the heart, lungs and liver. Place the juniper berries and the thyme inside the duck and season it with salt and pepper, inside and out. Truss it with kitchen string.
Put the wing tips and the neck chopped into pieces in a roasting tin just large enough to hold the bird and lay the duck on its side on top. Cover it with 20g (¾oz) butter and place it in the hot oven. After 8 minutes, turn the duck over on to the other side, and after a further 8 minutes place it breastside up and cook for a further 10 minutes. This operation sears the duck all over and causes it to shed the excess fat in its skin.
Remove the duck and let it rest in a warm place for 10 minutes. Throw out the fat from the roasting tin and pour in the red wine, leaving in the wings and neck. Boil for a few minutes to deglaze the pan of the meat juices. Then put on one side.
Remove the legs from the duck, cutting the skin carefully with a sharp knife, and set on one side. Remove the wishbone with the point of a small sharp knife. Skin the duck completely. Then carve five long slices from each breast, working parallel to the backbone (these are called ‘aiguillettes’). Keep hot.
Take the carcass of the duck and remove the heart, lungs and liver, which should be set aside on a chopping board. Remove the juniper berries and the thyme and add them to the juices in the roasting-tin (3). Chop up the carcass with a heavy knife or cleaver. Heat 20g (¾oz) butter in a saucepan and throw in the chopped carcass. Stir the pieces about so that they brown all over. Add the four coarsely-chopped shallots and the tomato puree. Let the shallots brown alittle then flame with the cognac. When the flames have died down add the wine from the roasting tin (3), together with the neck and wing tips, and boil till you have no more than a coffeecup of liquid left. Add just enough hot water to cover the bones, and put in the stock cube. Boil for 20 minutes. Meanwhile, chop the heart, lungs and a quarter of the liver finely (keep the rest for the cat). When the 20 minutes is up, strain the contents of the roasting-tin into another saucepan through a fine wire sieve and then reduce again until no more than a coffeecupful of the liquid remains. Add the chopped heart, lungs and liver, bring to the boil again briefly and strain again, into a bowl. Season with a few turns of the pepper-mill – the sauce should already be salty enough – and keep the sauce hot in a bain-marie.
A quarter of an hour or so before you want to eat the dish, season the duck legs on the flesh side with coarse salt and grill for 15 minutes. During this time, divide the sauce between two hot plates and lay five slices of duck (4) on each, making sure they are well bathed in the sauce. Put in the hot oven for a few minutes to heat through and serve. On a second plate, put the grilled duck legs, served simply with a green salad (curly endive or escarole) seasoned with wine vinegar and walnut oil.
Sturdy red wines: Burgundy (Pommard) Bordeaux (Margaux) or possibly Côtes du Rhône (Côte-Rôtie)