"I feel like I’m in kindergarten,” says the tall blonde, her tone inflected with bourgeois shock and awe. She and her date arrive for dinner on time but are shooed away by Canteen’s hostess, who insists they hold tight until the entire restaurant can be seated simultaneously. So they join the other diners awaiting the 7:30 seating—some patiently, some growling like their stomachs—in the lobby of the adjacent Commodore Hotel, a somewhat creepy place despite its elegant molding and festive blue, yellow, and green carpeting.

The fact that patrons wait happily in the jaundiced light and gritty décor of the Commodore—a former art school dormitory and a setting for a horror film if there ever was one—speaks volumes about the culinary talents of Dennis Leary, the chef-proprietor of Canteen. It’s a 20-odd seat diner with a haute cuisine attitude, a smartly refurbished dive that delivers some heavyweight palate-punching. Canteen’s schizophrenia makes some people love it and some rabidly confused by it. Leary admits his pedigree as former head chef of Rubicon, one of San Francisco’s most heralded restaurants, leaves some demanding patrons “pissed off” at the cramped diner environment. But this juxtaposition of high and low, eccentricity and excellence reflects Leary’s true nature, and Canteen’s identity crisis is part of what makes the tiny restaurant a Bay Area treasure.

The solitary waitress repeats the primary Canteen by-laws to each party: review the menu and order the whole meal at once so that things are properly timed. The menu lists four appetizers, four entrees, and four desserts, and a small but solid selection of French and California wines. No brand names of organic farms or fisheries; just simple descriptions.

The menu also showcases Leary’s puckish personality and, to Canteen regulars, a rotating repository of in-jokes. An occasional kitchen helper is called Chef Emeritus, obscure holidays like National Dance Day are duly noted, or a free dessert is offered to any customer who does a certain number of pull-ups. It also tracks the weeks since Canteen’s opening, although Leary admits he’s not sure if the number is accurate.

The formal font and dominant location of “Week 99” on the menu is both funny and brilliant. It throws a jab at old restaurants whose longevity claims imply greatness, and acknowledges the weekly struggles of a restaurant. It both celebrates Leary’s accomplishment and underscores the inevitability of Canteen’s demise. Hopefully, Leary will control his next venture as tightly as Canteen, where he selects ingredients, designs the daily menu, and cooks each dish with the aid of one assistant.

Canteen is one of the tiniest, funkiest restaurants you could visit, with seven seats at the key-lime green Formica counter and four modest booths with pine tabletops. The booth wall has pine bookshelves mottled with old books, and repeat customers treat it like a lending library. There are some odd vintage paintings, a coat rack, and a medical display case with featured wines and a huge, old dictionary. These decorative accents, like the menu, reflect both the literary heartbeat of San Francisco and Leary’s dry wit.

The arrow-shaped sign on the rear wall directs your gaze toward Canteen’s four-burner stove, the main stage of this curious play. There might be six square feet where Leary and his assistant dive around each other with capoeira moves, their hands and eyes intensely punctuating acts of grilling, flipping, pouring, plating, slicing, and dolloping. It’s a terse, modern ballet; a psychic surgery; a culinary kung fu. There’s almost no room to move and, thus, no room for error.

Both men know their assignments precisely. Leary’s assistant anticipates what’s next and makes the plates ready for the master’s hand. For all the physical frenzy, the performances seem ironically relaxed. There’s no verbal sparring or yelling; in fact, I never noticed Leary saying anything to the cook at all. (He well may have; during most of the meal, I was softly moaning with my eyes closed.)

I finally look around to enjoy the mix: 20-something hipsters, 30-something locals, 50-something gourmands, and a pair of lovers on a fourth date. Every night differs but in a good way, and sometimes the veils of intimacy between strangers drop entirely, transforming Canteen into the best privately catered party you’ve been to all month. It’s a fun, smart, unpretentious place, much like Leary and the people who eat here.

The food-loving community that’s rallied around Leary also shares his wide palette. There’s more significant chef-patron dialogue here than other restaurants, but the onus is clearly on the eaters to begin the conversation. When Leary recognizes an adventurous regular in his reservation book, he’ll order something unusual in advance, like lamb’s tongue from Montana or a few sea urchin or scud from Rhode Island. He may just have three of the special dishes to serve that night, but almost as often, he’ll give them away. That isn’t just an amuse-bouche; that’s amore.

Leary admits he’s bored easily, and he cherishes those patrons who share his passion for new ideas. His food knowledge is encyclopedic, so he also enjoys reinventing odd classics that have significant historical and cultural undertones. Sometimes for brunch he’ll serve Kedgeree, the English country manor breakfast of smoked fish, rice, hard-boiled eggs, herbs, and butter, based on an ancient Indian morning meal called khichri, which was mostly herbs, lentils, and rice. Now there’s a dish that changes breakfast conversations considerably.

Canteen is humor and energy, history and community, and among the best food you will eat in any restaurant, anywhere. Leary endures his hype with a shrug, but he’s one of the few chefs that consistently deliver food beyond expectation. One fun thing about Canteen is that you can dare to order things you normally loathe (cold fish soup, for instance), and you simply melt at how absurdly good they are in Leary’s hands (and in your mouth).

Canteen quiets a bit during the dessert phase, and when I look up, Leary’s on break. The guru has left the building; at least, until the last service at 10:15. A female executive sitting next to me sums up her first experience here perfectly: “Canteen is world-class eating,” she says. “You’ll have a lot of fine dining experiences in your life, but most are forgettable. You won’t often have eating experiences like this.”

Near us on one end of Canteen’s counter a kitschy harlequin lamp stands defiant: arms crossed, legs parted, a wicked, subtle smirk curling beneath his black mask. He is self-aware and confident, challenging and charming, and in complete control. I think Canteen’s designer knows Dennis Leary well.