Not even the city's top chophouses, with their jewel-encrusted strips and gold-flecked spuds, have whipped up a sauce as luxe as this one. Rodney Murillo, executive chef at Avila (One Charles Street South, Boston, 617.267.4810), is seeing their rich béarnaises and bordelaises and raising them with a duck stock he reduces with sautéed goose liver, red wine, and fresh herbs, then finishes with a further infusion of foie gras. It's just the stuff to soup up your hot rod of a sirloin.
