I don't have a whole lot of lobster roll experience. It's a New England or, more expansively, East Coast thing and I grew up on the other coast, where I'd never even heard of them. Just before my first trip to Cape Cod last summer, I asked around to find out what regional food was de rigueur on the Cape. "You HAVE to try a lobster roll," one Bostonian friend said. I promptly envisioned some kind of charcuterie made from lobster meat, something that might look like head cheese, or maybe a lobster bologna made from the crustacean's less glamorous parts. I didn't picture chunks of fresh lobster piled onto a butter-soaked bun, or the cold version: peony-pink, mayonnaise-based lobster salad tucked inside a rolled up piece of white bread.