For historic continuity, ferociously loyal community support, and an atmosphere that you could spread with a knife, you can't beat the hamburger joint Louis' Lunch, in New Haven, Connecticut. Since 1898, the Lassen family has been grinding its own beef daily, hand shaping patties to order, and grilling burgers on antique cast-iron broilers in front of live flames. (This answers the question once and for all — the proper way to cook a hamburger is by grilling, not by frying it on a griddle.) And as any regional American culinary landmark should be, Louis' Lunch is sufficiently quirky to allow melted processed cheese but militantly prohibit ketchup and mustard as accompaniments to its signature burgers.