Oh, memories are build here! Original French Pièce de Boeuf, just plain, grilled, with just a pinch of salt
The good thing about French supermarkets, yes those big ones, is that they stock a lot of high end market, high quality products. This goes for fresh veggies, but similar for wine and meat. In all, the French supermarkets are well catered for the "Gourmand" (the lover of all good food).