After sitting dark and lifeless for 18 months, one of the Twin Cities’ most spectacular dining venues is back in business. Let’s all share a collective sigh of relief.

The real estate in question is the magnificent grown-ups’ playground inside the tony Minneapolis condominium building known by its address, 510 Groveland.

Simply turning the lights back on at the former La Belle Vie wasn’t enough. The building’s residents held out for a quality operator on the premises, and they chose wisely when they recruited chef Don Saunders, who operates the Kenwood, a nearby neighborhood gem. (Although, in the Get Real Department, there was never any worry that this glorious square footage was ever in danger of becoming a Panera Bread franchise.)

Saunders, in turn, has assembled a promising team — including chef Daniel Keenan and pastry chef Jo Garrison — and thought long and hard about a business model that would honor the address’ storied history (pre-La Belle Vie, it was home to the 510 Restaurant, the epitome of 1980s and ’90s special-occasion dining) and respond to the prickly demands of the current consumer.

His formula makes sense, focusing on libations and libations-friendly fare in the lounge, seven nights a week. Given fine dining’s nose-dive, Saunders dropped the notion of running a restaurant in the dining room, reserving that space for private events. The new name crisply encapsulates the business: 510 Lounge & Private Dining.

The lounge’s menu is at its best when it embraces shareable and/or small-scale dishes — starting with caviar. It’s a no-brainer, given the sumptuous surroundings, and Saunders and Keenan really do it right.

They accentuate farm-raised versions in the sturgeon family, culling five options from sources domestic (the chilly waters of Idaho’s Snake River) and foreign (earthy olive-green Osetra) and serving them with the proper accoutrements: tangy crème fraîche and tender, barely warm blini.

At least for now. Saunders, a traditionalist who isn’t afraid to venture into new territory, originally subbed out the blini with an unorthodox element: crisp, golden potato chips. It didn’t last long.

“There was a decent amount of feedback from customers ordering the Osetra, saying that it felt weird to be eating potato chips with such an expensive product,” Saunders said.

Now he’s thinking that the chips might be making a comeback. “Maybe we pulled the trigger too soon,” he said with a laugh.

Of course, caviar is the very definition of indulgence — in the $55 to $150 range — so it’s a bummer that they’ve dropped what I considered their Intro to Caviar option, a coral-tinted, large-pearl trout roe for the (relative) bargain of $25.

Cheese, please

The kitchen also has a reliable nose for cheeses and cured meats — the menu features a half-dozen or so options in each category — constantly rotating through regional, national and international sources.

They’re served individually or in big, beautiful blowout platters, and paired with an imaginative flurry of just-right mustards, pickled vegetables, preserves, nuts and fruits and top-shelf Baker’s Field breads.

Right now, don’t miss the cow’s milk miracle that is Wisconsin cheese­maker Willi Lehner’s cave-aged bandaged Cheddar, or the Camembert-style sheep’s milk cheese produced near the shores of Lake Superior at the Bayfield, Wis., farmstead operation that Fred and Kelly Faye have dubbed Happy Hollow Creamery. On the meats side, the supple, fat-streaked ham from southwestern France is a must, as is the kitchen’s own luscious veal terrine.

The shareable vibe continues with a handful of frequently imaginative ideas. I loved the cool, dense raw tuna, draped over cauliflower that was chopped to the consistency of quinoa and brightened with an acidic sauce. A crisp toss of endive and Honeycrisp apples made for an ideal autumn palate cleanser.

There are excellent, eat-every-­single-one fries, and tantalizingly salty olives. An amusing curiosity is delicately crispy croquettes made with a surprise ingredient: black rice.

Keenan and Saunders round out the menu with a half-dozen entree-size plates, a hedging-their-bets move that feels slightly out of place, but is clearly targeted to those who might not go all in on the lounge menu’s grazing vibe.

Sure, it’s difficult to find fault with a fork-tender and intensely flavorful flat iron steak (or its rollicking chimichurri sauce), or a simple slab of roast salmon (a shoutout to a long-ago 510 Restaurant favorite), or a superb lamb burger (an homage to a La Belle Vie standard, the lean meat fattened with beef and butter, and served on a dreamy, brioche-like Baker’s Field bun) or an instant replay of a Kenwood signature dish, plump mussels steamed in white wine and cream and finished with the timeless combination of garlic, basil and olive oil.

Or a dazzling tart. It combined garlicky creamed spinach, cultivated and foraged mushrooms, caramelized onions and a poached egg. Finished with an earthy dried porcini vinaigrette and shavings of fall black truffles, it was one of the most satisfying vegetarian dishes I’ve encountered in ages.

But all the while I couldn’t help but feel as if I was overdoing it. Rather than present the 510 as a full-fledged restaurant (one that offers, say, a hefty venison chop, dazzling as it is), it makes more sense to follow the spirit of the lounge atmosphere and emphasize share-with-pals dishes.

A tartine, piled with velvety smoked trout, made an earlier appearance on the menu, and it was exactly the kind of lighter, communal fare that feels more suitable to the surroundings.

Making pretty even prettier

General manager Peter Beard’s discerning, around-the-world wine list immediately qualifies the 510 as one of the region’s better wine bars.

It features 19 by-the-glass options, most sold in full- and half-size portions; the latter is an encouragingly affordable path for perusing the roster (although there isn’t one full-size glass under $9, or a single bottle under $40; what’s with that?).

The cocktails, most of them modern takes on classic libations, do the room proud.

Yes, the room. Here in Teardownapolis, this 1927 patrician stunner — it’s the physical evocation of a trust fund — stands tall because so much of the rest of the city’s elegant past has been mercilessly bulldozed.

It also happens to be gorgeous. Talk about great bones: Tall windows, brass chandeliers dripping in crystal, a doozy of a fireplace and a soaring ceiling decorated with State Capitol-levels of elaborate crown molding are just some of the details that make the place stand out.

A respectful upgrade, directed by the Minneapolis design firm of Smart Associates, injects some playful notes into the socialite proceedings, without going overboard.

Lively textile patterns borrow from the haberdasher’s vocabulary (herringbone, houndstooth) and walls are decorated with attention-grabbing prints by Minneapolis photographer Shelly Mosman. Those cute plaid lampshades on the bar? They’re a visual shout-out to the plaid wallpaper at the Kenwood.

The warm, buttery yellow walls of the La Belle Vie era have been repainted a rich dove gray (FYI, it’s Benjamin Moore’s Stormy Sky, in a satin finish), a switch that really accentuates the paneling’s details.

A bracing splash of color comes courtesy of a no-holds-barred red (with animated pink undertones) that seems to leap off the surfaces of a small overflow dining area. Designer Jim Smart calls it the Jackie O. room, and the color is so vibrant that it surely resembles the interior of a corpuscle.

Comfortably proportioned booths create additional table seating. Even when a full house is going full-tilt, the noise level doesn’t overwhelm. Oh, and post-sunset, the illumination is Lancôme counter-quality levels of flattering.

On the private events side of the building, Saunders & Co. are hoping to supplement an already steady stream of weddings and wedding rehearsal dinners, corporate events and wine groups with pop-up, open-to-the-public dinners. First up? A seven-course tasting menu on New Year’s Eve.

As for dessert, Garrison’s sculptural, cerebral work frequently exhibits a keen sense of texture and a clear (and welcome) aversion to too-sweet sweets.

I didn’t adore everything I sampled, but I admire her ability to get in the last word, literally, by approaching dessert as a conversation starter.

What a fine way to wrap up a visit to this conversation-inducing place.