What on Earth is a hamburger sandwich and why is it significant to New Haven?

You have to start with the invention of the burger. It would seem impossible to pinpoint exactly when cooked patties of ground meat were invented, but it’s safe to say it happened a long time ago, in a faraway land: Mongolia, possibly, or ancient Egypt perhaps. More recent than that, it’s been associated with Hamburg, Germany; according to The Oxford Companion to Food, along with the wave of German immigration to the U.S. in the early 19th century came something called “Hamburg steak” (ground beef) on New York restaurant menus.

As far as who was the first to put said ground-beef “steak” between two slices of bread—a food now widely associated with America—there are, not surprisingly, several competing claims. One of the most likely stories originates here in New Haven, with a small luncheonette called Louis' Lunch where the same family uses the same broilers and serves the same “hamburger sandwiches” that they claim they invented back in 1900. (Even more of these claims have surfaced in recent years, casting a bit of doubt on Louis,' but there's no question this was one of the first!)

So a hamburger sandwich in New Haven is what's served at Louis' Lunch: a lean ground-beef patty cooked in a (now antique) vertical broiler and placed between two slices of white toast with tomato, onion, and optional cheese. No bun, no ketchup, no mustard—just a unique, century-plus-old local take on a burger.

Where: According to Louis’ Lunch (261-263 Crown St., map), established in 1895 as a lunch wagon, owner Louis Lassen invented the hamburger sandwich one day in 1900 to meet the request of a customer who wished to eat on the go: Louis placed his own blend of ground steak between two slices of bread, and a legacy was born.

The small, boxy, brick luncheonette that is Louis’ today hasn’t changed much over the years, although in the 1970s it was fully relocated (as in, the whole building was picked up and moved) to its current location after coming under threat of demolition from a new high-rise—and it’s hard not to love every timeworn, initial-carved inch of this place. Nowadays, the man in charge is Jeff Lassen, a fourth-generation family member who cooks your burger in the same antique cast-iron broilers his great-grandfather once used.

When: Tues-Wed, 11am-3:45pm; Thu-Sat, noon-2am

Order: One “ham works” ($5.50), which is Louis speak for a burger with sliced tomato and rounds of grilled onions between slices of Pepperidge Farm white toast. Get it “cheese works” to add the only cheese available here, a Cheez Whiz-like spread. (Due to the vertical grilling method, any other cheese wouldn’t work.) Those are the only works; don’t even think of asking for ketchup or mustard here—they don’t have it.

The meat, a hand-shaped blend of five meats, somehow stays moist and flavorful despite being grilled upright in vertical broilers—which are kind of like precursors of the Lean Mean Grilling Machine, with excess fat dripping out—but keep in mind that the “medium rare” baseline here tends to be pretty darn rare (despite the raw look of the photo, the meat is hot). Onions are grilled simultaneously with the meat in the 1898 broilers, while the bread gets warmed in a circa-1929 antique revolving toaster.

Pull up one of the few seats, and pair your burger with a local Foxon Park soda—cream, grape, root beer, birch, gassosa (an Italian lemon-lime flavor)—and some of the excellent homemade potato salad, with hard-boiled egg and chive. For dessert? Try the homemade pie and you’ll have sampled nearly the entire menu.

Good to know: Buns aren’t used here because Louis never used ’em: They were invented decades after his sandwich was born. As for condiments: The restaurant claims it doesn’t offer them not only because Louis never did, but also because they’re all about the “taste and simplicity of a good burger grilled to perfection.” It’s true that the burgers taste of good-quality meat and the broilers do them justice (though we’ll request ours cooked a bit longer next time), but we couldn’t help thinking this good burger would become great with just a little ketchup or mustard thrown into the mix.

It may be a little over-the-top, but we admire the current owners’ steadfast adherence to tradition—although, as Serious Eats points out, the cheese spread was not a part of Louis’ original burger, but came along in the 1970s. You don't come to Louis Lunch just for the burger; you come for the unique opportunity to taste culinary history in a time capsule of a restaurant. For that, it’s a worthwhile visit for any hungry traveler in New Haven.