Part burger, part Filet-o-Fish, with a bagel and lox thrown in for good measure, the Captain Hook ($15.50) at Holsteins in Las Vegas is one hulking hybrid of a sandwich. Grilled Atlantic salmon (best ordered medium rare for ultimate buttery richness), dressed with crisp frisée, tangy pickled shallots, and a creamy caper-herb mayonnaise that's just this side of tartar sauce, in all the right ways. In Vegas, more is always better, so the salmon fillet is then topped with a really generous slab of house-cured gravlax. More