Let’s clear up any confusion associated with Union, the multilevel extravagance that Crave parent company Kaskaid Hospitality launched last fall in the former Shinders building in downtown Minneapolis.

The rooftop’s gasp-inducing expanse of barrel-vaulted, retractable glass is its own self-contained restaurant and bar. The basement is devoted to Marquee, a weekend-only nightclub. And the street-level dining room (previously shorthanded to This Is So Not the Fabulous Rooftop) has been repurposed as Union Fish Market.

The transformation further cements Hennepin Avenue’s reputation as a dining destination. While this newcomer may lack the atmospheric fireworks of its upstairs counterpart, chef/rising star Lucas Almendinger more than compensates with some impressive culinary pyrotechnics.

Almendinger, 30, didn’t start out in chef’s whites. He studied guitar making before becoming a furniture maker. About five years ago, the South Dakota native began to feel restless. “I had a good job, but I wasn’t excited when I went to work,” said Almendinger. “I decided to follow cooking and see where it led.”

His impulse proved fortuitous. Almendinger immersed himself in a veritable on-the-job master’s degree program in the subject, learning from a series of mentors, culminating in the chef everyone wants as their unofficial culinary school faculty adviser, Steven Brown at Tilia. He cooked alongside Union’s opening chef, Jim Christiansen, and when Christiansen departed (for the debuting-next-year Heyday), owner Kam Talebi wisely promoted Almendinger.

“I love working with fish,” Almendinger said. “It’s so versatile. You can work exclusively with salmon, for instance, and you’ll never exhaust the possibilities.”

A celebration beyond the ordinary

Combining that unbridled enthusiasm with what is clearly a healthy imagination and obvious technical prowess, Almendinger is turning out dishes of great distinction. Skate, which gets far too little play in the Twin Cities, is prepared as a tribute to trout meuniére, with brown butter and capers, the crispy browned exterior giving way to scallop-like succulence. I could gleefully consume it on a daily basis.

Scallops are a joy, with the harmonious flavor of smoky bacon sneaking in between tastes of roasted and pickled beets and crunchy candied pistachios, a deftly balanced tango of sweet and tangy. White gazpacho, charred cabbage and colorful pickled grapes are ingenious complements to moist, flaky sea bass. Shishito peppers’ gentle heat, yuzu’s acidic bite and carrots’ natural sweetness all work in concert to enhance a buttery, deeply flavorful salmon.

Soups, meticulous in their composition and dramatically presented, are a joy to behold. Juicy soft-shell clams, butter-poached potatoes and a silky sunchoke purée, lightly seasoned with clam juice and lemon, work a stunning transformation on clam chowder. Even more impressive is a refined sweet potato bisque, enriched with lobster stock and sweet poached lobster meat. Golden, smoky steelhead roe and bits of fresh chervil are upstaged by a gossamer tuile, which slowly dissolves into the soup’s heat. It’s spectacular.

Both are cornerstones of the menu’s small plates roster, each one a minor triumph, and most of them inventively incorporating pristine seafood. The textural connection between pork and sturgeon is played up in don’t-miss rillettes, the fish hot-smoked and cured in brown sugar and salt, then capped under creamy rendered beef fat, for spreading over lefse (an Almendinger family favorite) and finished with bright lingonberry and mustard accents.

I can’t stop thinking about the plump Manila clams, steamed in a teasingly smoky dried chorizo broth. Or the cute riff on the bánh mì, with cool, succulent lobster playing against a rich smear of chicken liver pâté. Or the ingenious, runny-egg-crowned Caesar salad, with baby kale subbing for romaine.

Then there’s the adorable homage to Red Lobster (“It was the only seafood option we had in South Dakota,” said Almendinger). It’s a hybrid of the State Fair and the classic Southern dish, shrimp and grits, all wrapped up in snappy jumbo shrimp, speared on a stick, battered in a cornmeal batter, rolled in cornmeal panko for extra crunch and fried into golden abandon. You cannot imagine how addicting these guilty pleasures are, particularly when smeared with a crazy-good blend of polenta, Dijon mustard and a squirt of yellow French’s mustard. Hello, ideal bar snack.

Variations on a familiar theme

American seafood bedrocks get their due. Snowy white cod, dipped in a beer batter and paired with vinegar-kissed russet potatoes make for a sublime fish and chips, and grilled bread sopped up every last drop of the robust broth that laid the foundation for Almendinger’s first-rate cioppino. A handful of straight-up grilled selections — salmon, trout, sea bass, lobster — are handled with tender loving care and accompanied by just-right sauces and a la carte sides (do not, under any circumstances, skip the potato puffs, or the Brussels sprouts).

While they sometimes try too hard, pastry chef Erik Lindstrom’s painstakingly crafted desserts — all pushing the outer limits at $9 — often possess the power to delight. Highlights include a wildly showy baked Alaska that reorders the campfire s’more (high-proof rum helps), a poached pineapple that runs all kinds of sweet-tart sprints and textural somersaults and a Southern-style stack cake utilizing lefse and lingonberries and served with delicate rosettes.

On the other hand

Speaking of flaws, a few dishes don’t quite work as conceived (too-tough abalone, served in its gorgeously iridescent shell, didn’t quite mesh with its brown butter treatment) while others (crabcakes crying out for a punchier crab bite) would benefit from modest tweaks.

The menu’s token non-seafood items — chicken, pork, beef two ways — are uneven at best, and none live up to their aquatic counterparts. There’s also the occasional sticker shock. I’ll miss the jaunty portable show-and-tell cart, wheeled tableside and heaped with raw oysters, poached lobster and steamed crab, all sold by the piece, and all intrinsically appealing. Its basic menu remains, but the actual cart proved difficult to navigate in the dining room.

While the setting lacks Crave’s patented visual hoopla — actually, almost nothing about Union Fish Market bears so much as a whiff of its formulaic corporate cousin — the generic brown-on-brown space still feels as if Kaskaid devoted the vast majority of its budget on the roof, leaving the austere first floor to a halfhearted once-over.

Frame the conversation this way: Does a diamond ring belong in a box lined with cardboard, or velvet? Almendinger’s exciting, nuanced work deserves — correction, demands — a more suitable platform.

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