A recent Friday at M. Wells.Photo: Jake Chessum

The dinner menu at M. Wells is coming together before my eyes. Good thing, too: It’s past 3 p.m., and dinner service starts at six. The chef, Hugue Dufour, is improvising a mackerel recipe in a thick Quebecois accent (“Sauce vierge, lots of sea beans, it’ll be great!”). A new cocktail, a sort of bullshot made with Vegemite, is created on the spot. A cook shells chickpeas, inches from a customer’s elbow.

There’s nowhere else to do it. Queens’s most-talked-about restaurant of the moment (and arguably ever) is stuck inside a grubby diner the size and shape of a city bus, on a weedy Long Island City lot a few hundred feet from the Midtown Tunnel entrance. The space, which seats 55, is featureless—not in the minimalist Dwell way but in the we’d-rather-cook-than-design way. The kitchen barely exists. The unfinished basement, reachable via a hole in the floor, houses cases of wine and one cook’s oil paintings. Electricity mis­behaves, water runs out. That anyone can keep the place going is impressive. That this is a restaurant that sends even hardened foodies into ­paroxysms of joy not seen since the dawn of Momofuku is almost incomprehensible.

When word came that there’s a place in Queens—Queens!—that serves marrow bones surgically implanted with escargot and covers summer soup in a layer of lardo and foie, the news had the tinge of the ­hipster-gourmet perfect storm: an offbeat locale, a cultish chef from an out-of-town restaurant, and haute cuisine slung like hot dogs over Formica. Dufour used to be a cook at Au Pied de Cochon, an haute-punk ­Quebecois emporium famous for putting foie gras on pizza, hamburger, and poutine; he brought the same maniacal high-low sweep to M. Wells. Every permutation of the menu is now chronicled by food blogs, and the wait for a seat for a Thursday-night dinner can top an hour. God knows what would transpire Friday and Saturday nights. M. Wells is closed then.

“I didn’t invent Queens, you know,” says Dufour as he pours a glass of his own house rosé, made by a friend in Costières de Nîmes. True. But the looseness at the root of M. Wells’s greatness is barely possible anymore elsewhere. Only here can a restaurant afford to survive its first half a year serving only breakfast while the liquor license is in the works, or stay shuttered on the week’s two most profitable nights. It’s not a statement, explains Dufour’s wife, Sarah Obraitis: “It’s an old building with no storage. The suppliers can only deliver in the morning, so there’s not enough room for the 200 covers we’d do on a full Saturday.” More important, she says, “The rent is low, and there are no investors. We can do whatever we want. And we don’t want to be here all the time.”

The amiable Dufour grew up on a farm in Lac St. Jean, six hours north of Montreal; the brash, surfer-girlish Obraitis comes from Queens. They met, of all places, in Orlando, at a private event (he cooked, she was the supplier). Dufour moved to New York in 2009. “I was done with restaurants,” he says. “I wanted to have a general store, with fur and skins. I’ve been hunting and trapping all my life, and I wanted a store where designers could get, like, fucking polar-bear skins. And we’d have toys for kids.” He pauses. “And just a little butcher counter in the back.” Another pause. “And we’d make meat pies for the winter.”

While that idea cooked, the couple fixated on the shell of a diner kitty-corner from their apartment. In its last pre–­M. Wells incarnation, it was a bodega and a Chinese takeout at once. When Dufour and Obraitis took over, they’d inherited a wok station (“We made everything in it”) and a Peking-duck roaster, which explains the menu’s spectacular but random Peking-duck dinner for four.

M. Wells (the M. stands for magasin, or “store”) opened on July 6, 2010. There was no concept. “We let the place dictate, and we let the cooks dictate. We were all over the place. It was a diner, so we started with breakfast.” At first, customers would walk in and demand things like egg on a roll. “I didn’t even know there was this whole culture!” says Dufour. “I had Twin Peaks in mind: coffee and cherry pie.” Undeterred, he started baking his own English muffins and working within the outer-­borough-diner idiom. Tortilla española, one of M. Wells’s biggest hits, is a survivor from those days; the Breakfast Hot Dog is a more recent descendant. What Dufour didn’t yet know was how far in his favorite direction (organ meats, fat, the flagrant use of foie gras) he could push things. New York, it turns out, lapped it all up. One day, “I had some veal brains sent over,” Dufour recalls. He turned them into a dinner plate that now sells out every time it’s on the menu.

The wok heat in the tiny kitchen is getting intense. Dufour’s black T-shirt, which depicts a penguin in a noose (a Montreal restaurant in-joke) is half-soaked. Back in Quebec, jokes Dufour, “I’m the new Celine Dion.” He’s referring to the fact that he recently got a letter from the province’s prime minister (“I thought it was about my taxes or something”) congratulating him on his success. Five minutes later, a camera crew appears: It’s Anthony Bourdain’s new show, taping beauty shots. Dufour lets them film, then sits them down and force-feeds them octopus salad. “It’s like this every day now,” he says with a shrug. “I don’t know! I worry what will happen when this dies down.”

Except, of course, Dufour didn’t really mean to get stuck in the restaurant business anyway. His next dream is a farm—a real one, huge, like the one he grew up on, not some sort of hipster backyard thing. Or, perhaps, a building project. “I want to build a diner,” Dufour says wistfully. “From scratch. And a hotel, maybe. Yes: I want a diner with a hotel.”