If I’ve learned anything over the past 14 years, it’s that Grant Achatz and Nick Kokonas rarely take the path you expect. With their newest offering, the St. Clair Supper Club, they’ve introduced a challenge for themselves: reinventing a genre that not many people were clamoring to see reinvented. Right under our noses, they transformed the cozy basement of Roister, the Alinea Group’s West Loop outpost, into a slick update of the traditional folksy supper clubs that once dominated the Midwest. With its leather booths, cartoonish paintings, and paper placemats that read “We’re Glad You’re Here,” Team Achatz isn’t after stars and awards. Heck, there’s a carved bear head mounted on the wall.

Achatz and Kokonas both grew up on supper clubs — Achatz in Michigan and Kokonas on visits to Wisconsin. Like any good Midwestern boy, I did, too. My parents have never forgiven me for the time my brother and I ate a million rolls and slipped away from a family dinner at a classic supper club near the dunes of northwest Indiana and proceeded to get sprayed by a skunk in the woods behind the restaurant. I heard the prime rib was pretty good that night, though.

By definition, a supper club — the “club” designation is merely a holdover from the era of Prohibition, not an indication that membership is required — isn’t meant to be cool, or even ambitious. And the St. Clair Supper Club, named for Achatz’s hometown of St. Clair, Michigan, trades heavily on no-nonsense heartland memories. The menu includes four appetizers, one entrée (prime rib, of course), and eight sides — and that’s it. Dietary restrictions or food allergies? Sorry, pal. Vegetarian options? Look elsewhere, unless you count mashed potatoes. Instead of trying to be all things to all people, or even some things to some people, the St. Clair exhibits such a stubborn laser focus that I found myself wondering if there’s any market for it in 2019.

The specialization starts with the cocktail list: nothing but martinis, Negronis, and brandy old-fashioneds. A supper club without a good brandy old-fashioned is just a sad family restaurant, and the St. Clair’s version, designed by beverage director Micah Melton, is traditional in a very good way, sparked by a floater of Sprite, just like in Wisconsin. Bar manager Mehdi Elahiparast’s bracingly smooth Negroni and killer martini, lined up across from nearly every diner perched at the kitchen counter, are equally first-rate.

A talented kitchen staff, led by Dan Perretta (Roister’s executive chef) and Mark Hopper (who worked with Achatz at the French Laundry more than 20 years ago), was charged with producing traditional supper club fare with no smoke and mirrors. Kokonas says he told the chefs: “You get three ingredients for creamed corn. If you’re so effing talented, then make it awesome.” They responded by getting corn that’s been picked within the last 24 hours at Mick Klug Farm in St. Joseph, Michigan, and putting it in a skillet bubbling with cream, cornstarch, and butter to produce an Americana-style Proustian ecstasy that’s as familiar as your childhood blanket, but better.

Same story across the board: eight Island Creek oysters Rockefeller with Nueske’s smoked bacon, Pernod, and baby spinach that’s been sautéed in shallots and Danish butter. The crisp crab cakes contain pure Jonah crab with no filler whatsoever, along with their usual sidekicks (a fried pickle, tartar sauce, and lemon wedge).

I kept waiting for the twist, the telltale hint of the chefs’ egos that would turn the restaurant insulting or perverse. It never came. Nor was there the slightest wink from the ebullient servers that any of this was being done ironically.

The pinnacle of it all, of course, is the prime rib. Though it’s cut from the same section of a steer as the ever-so-trendy rib eye, prime rib has long been banished to the dusty realm of Old People Food, the prize of early birds and blue-hairs at Lawry’s. My dad requests prime rib for his birthday dinner every year. I bet he’s never had anything as good as the St. Clair’s four cuts, which have all been briefly aged in Roister’s walk-in, then seasoned for a day or two and cooked medium rare. (Do not attempt to order yours well done. The kitchen simply will not do it.) The standout is the English cut, layers of pink and silky flesh that are every bit as decadent as the glorious cap of fat that rings them. The intensely brothy aftertaste is a whisper from the gods, the result of the chefs’ countless hours tinkering with the jus while they obsessed over finding the perfect umami flavor without oversalting. I’d say they found it. For years, Kokonas has wanted to start a company called One Thing Well, which would encompass a series of single-item restaurants — burgers, ramen, and so on — that serve a truly great version of one dish. The St. Clair Supper Club is sort of the prime rib version of that.

Now. The prices. In choosing this approach and concept, the Alinea Group basically put a great big “Kick Me” sign on its back. To anyone old enough to remember the glory days of supper clubs, much less long for them, the idea of paying $75 for prime rib and $16 for a slice of grasshopper pie at a persnickety-sounding hot spot in a flashy neighborhood makes for an easy target. You have to buy tickets to the place, for crying out loud. But the St. Clair Supper Club brings the same level of attention to a Caesar salad as Achatz does to Alinea’s iconic edible balloon, and for what it’s worth, the restaurant’s cost per dish relative to retail price is the highest in the company, Perretta notes.

Instead of shooting for the moon, the St. Clair Supper Club painted the golden glow of nostalgia onto a shiny new canvas. It’s not just 180 degrees from Alinea; it’s 180 light-years. Turns out that’s a surprisingly good place to be.