Season the beef with salt and pepper on both sides, and rub in the seasoning with the tips of your fingers.
Heat a generous tablespoon of butter in a frying-pan and when it begins to foam put in the beef. Lower the heat so that the meat does not acquire a hard crust, and cook for 5–10 minutes each side, depending on the thickness of the meat and how well done you want it. Take care that the butter does not burn.
Remove the meat and keep it hot. To do this put it on an upturned plate placed inside a larger one, and cover the whole thing with an upturned bowl. This allows the meat to rest without drowning in its own juices, which would spoil the texture.
Pour away the cooking butter and replace it with the remaining butter, together with the chopped shallots. Return to a medium heat and allow to soften for 5 minutes, without allowing the shallots to brown. Add the wine vinegar and cook for a further 5 minutes, stirring with a wooden spoon. Season with a few turns of the peppermill and salt if needed. Add the chopped parsley and the juices which have run out of the meat (3). Mix well with a wooden spoon and pour into a sauceboat. Keep hot.
Cut the beef in thick slices, giving each person an equal quantity of lean and fat. Serve very hot, accompanied by the shallot sauce. This dish is especially popular with meat-lovers and needs only a salad of curly endive seasoned with a mustardy vinaigrette. And if the accompanying wine is cool and fresh I promise you a splendid meal.
Light red wines (new Beaujolais or fairly young Saint-Estèphe)