The most interesting thing about this version of canard aux navets — duck served with turnips — is the way I cooked the turnips. The duck consists of a couple of leg-and-thigh sections (cuisses). That's one per person. The package I bought contained two such pieces plus four wing pieces, and a little packet of dried thyme. I'm saving the wing pieces for later.
So for the duck legs, you just brown them skin-side down in a hot frying pan. You can put some oil or butter in the pan if you want, but it's not required. When the skin has turned a golden brown color, it will have released enough fat for the fleshy side of the legs to cook without sticking to the pan. You can put in some chopped onion, celery, and herbs at this point. (Substitute chicken or turkey if you can't easily get duck.)
After browning the duck pieces on both sides, add some liquid to the pan — water, white or red wine, broth, or a combination — and let the legs cook, covered, either on top of the stove or in the oven until they are well-cooked and to your taste. Season them with salt and pepper, of course. Long, slow cooking is best, I think.
If you want turnips with the duck, which is a classic combination, cook them this way: peel them and cut them into thick slices — say 2 centimeters (¾ inch). Put them in a pan in one layer and pour in just enough water to come up to the top of the slices without really covering them.
Dot the turnips with a tablespoon or two of butter cut into little cubes. Season them with salt and pepper. Add a tablespoon or two of honey. Turn on the heat to medium high. Leave the pan uncovered. By the time the water evaporates, the turnip slices will be cooked to a fairly tender stage. Check them for doneness with a skewer or the point of a small knife.
Leave them in the pan, and the slices will start to brown — caramelize — and turn a golden color. The slices will be glazed and sweet... almost candied. Turn them over to brown both sides. At this point, turn the heat off as soon as they are nicely browned. You can serve them immediately or leave them in the pan and just reheat them when the duck pieces are ready to be taken to the table.