Beef Filet with Wine Sauce

In this version of carbonade, the beef-and-wine dish that is a hallmark of Valdostana cuisine, the principal elements are cooked independently. First, you prepare the sauce, cooking red wine with aromatic vegetables and herbs until complex in flavor and highly concentrated. Later, the beef tenderloin, the filetto, is skillet-roasted (on the stovetop) until crusted and caramelized outside and juicy inside—a simple cooking method that takes barely 15 minutes. Before serving, you deglaze the empty skillet with the wine sauce and blend in the butter. It is only on the serving platter that the beef and wine come together, yet the pairing is perfect. I particularly like this separately cooked wine sauce because it is as good with other meats as it is with the filetto. Try it with roasts, such as loin of pork or rabbit, or with game, such as tenderloin of venison or elk, seared like the beef tenderloin here.