At Old City's Tuna Bar, sushi, a sleek space, and a side of Fujianese family flavors

He studied to be in finance. But Kenneth Sze, who now intently oversees the live sea urchins, Wagyu beef, and flaming salmon at his new Tuna Bar in Old City, says he was born to be in the restaurant business.

By second grade, he was manning the egg roll deep fryer at his parents' Great Taste Chinese takeout restaurants in Delran and Maple Shade. By fifth grade, he was stir-frying rice over the jet-fired woks, barbecuing pork, and making wontons: "I did it all," says Sze, 33, who also began making deliveries from the moment he had his driver's license, and, as a middle schooler, helped his parents overcome the language barrier to understand their restaurant leases.

"We basically did the American Dream route," says Sze, who was also behind his family's next step into the world of sushi and hibachi at Yokohama, a Maple Shade standby that has garnered accolades from multiple South Jersey publications. "My dad worked as a waiter at a French restaurant, then opened his own places. I went to college. Did everything immigrant parents want for their kids to grow up and do."

And so the last thing his parents wanted him to do, he said, was to open a restaurant. "My parents were so against it," he says. "But they are to blame!"

A budding finance career after his studies at Drexel was detoured by the demands of his family restaurant, where he stayed. So when it was time to bet his savings to realize his own dream, he says, it would reflect the world he knew best — a restaurant that it is at least as much American in its fusion bistro vibe as it is influenced by Japanese traditions and his family's Fujianese roots. And his Philly debut at Tuna Bar is just that, a stylish modern space designed by Boxwood Architects with blond wood, stone, and glass in the new Bridge Building that is another worthy entry for resurging Old City that has broad appeal, whether you like your food raw, cooked, or shaken into a trendy cocktail (like the electric green cucumber and wasabi drink Winston's Heat).

On its surface, Tuna Bar is, of course, focused on sushi, and that aspect is well served by Sze's longtime responsibility for shopping each morning at the fish markets for his family's restaurant, which was too small in its early days to receive deliveries. It's a practice he's continued here, and the quality of the raw ingredients is excellent, from the yellowfin that gets pounded into a purple disc of crudo splashed with truffled ponzu, crunchy rice pearl beads, and curry-fried burdock root to the luscious bluefin toro, alabaster hamachi, and fat-striped orange slabs of Tasmanian trout that get served as sashimi. Richly marbled A5 Wagyu beef is treated with the same reverence as a prized piece of toro belly, sliced sheerly and draped over a nub of ngiri rice, which absorbs every drop of buttery fat when the scored meat gets lightly torched.

The specials list is often full of surprises, including my first taste of slender cornet fish, whose dusky flesh has a firm texture without being too chewy, and which was smartly contrasted by minty shiso oil and juicy bursts of ruby grapefruit. A live giant surf clam was sliced into a mound of thick and fleshy threads that were both briny and sweet, and so fresh they actually twitched when our server reached over and poked them with chopsticks.

It was an admittedly startling moment, and not just for its slightly creepy illustration of what consuming shellfish that was living just moments before it met the sushi chef's knife actually means. It was also odd for the sudden burst of enthusiastic attention from a service staff that was so scattered and disorganized they had forgotten us altogether, neglecting to bring us water, let alone say "hi" for nearly 20 minutes after being seated.

"So, what does that taste like?" she asked us about the cornet fish, making it all too obvious this staff receives little to no training. With that in mind, I can forgive her for insisting the raw kumamotos came from Japan (they were from the West Coast), or that the katsu fried oysters were "from the city." Hmmm … hopefully, far enough up upstream from the sewage treatment plant.  (They were from the West Coast, too.)

The drink program is also in need of some extra fine-tuning, with room for more clarity in some of the Asian-inflected cocktails, which occasionally bordered on dull, and a closer hand on keeping lists current. I requested three things in a single meal (a Japanese beer and two sakes) that were no longer available. (Hint: the Hitichino Nest white ale never fails, and a biodynamic Montinore pinot gris was also a good choice.)

"I can see why my parents were against this — it's hard!"  Sze says, acknowledging he's been seriously challenged to find and manage a solid front-house staff. He brought chef Ronny Huang from Yokohama to oversee the sushi bar, and though Huang does a fine enough job, and the ingredients here are prime, I would not classify Tuna Bar's sushi craft as among the city's elite in terms of originality. Oft-overlooked Kisso a couple of blocks west on Race Street is an equally good, if more minimalist, BYOB sushi option.

There are nonetheless some good rolls to be had, including the Sindy, named in honor of Sze's mom, Cheuk Sin Chan, a special from Mount Laurel that wraps crunchy eel, avocado, and mango in a sheet of purple bluefin tuna in lieu of the usual seaweed. The Old City Roll tops a spicy tuna-asparagus roll wrapped in soy paper with crunchy, creamy rock shrimp, which adds up to a mouthful for each piece, but a tasty one. The smaller peppered tuna tuna roll drizzled in white wasabi aioli was also satisfying.

But some of the most memorable dishes at Tuna Bar were cooked –  or still cooking, if you count the seared king salmon shokiyaki that arrived at the table over a sheet of cedar paper that was in flames. Its sweetly aromatic wisps of smoke added a novel sensory flourish to an otherwise familiar dish of teriyaki salmon. Sze's take on teriyaki beef is upped by the quality of the steak, a 14 oz. bone-in N.Y. strip of Black Angus that was tender and full of flavor. At $35, it is by far the priciest item on Tuna Bar's menu.

Some of my favorite dishes, though, were far less expensive, and spoke to Sze's Chinese roots. The excellent pork gyozas were essentially his family's dumplings updated with good Kurabuta pork touched with ginger and a splash of Fujianese wine. The chicken and shrimp dumplings sparked with long chives were delicate.

The excellent stir-fried rice dishes, meanwhile, hark back to the days when little Kenneth the fifth grader learned at the side of his father, Ka Keung Sze, who taught him the secrets of skilled wok-craft, where searing high heat and clean pans magnify the character of every grain of rice and nugget of protein into potent jewels of flavor. Whereas spare bits and leftovers were the feature in his youth, Sze upgrades these stir-fries with tender chunks of lobster tail, or fresh peas, plump shrimp, sweet Chinese sausage, and a fried egg for "mai fried rice."

But no dish speaks to Sze's family pride more than the tiny dumplings and restorative brew of "Grandmom's Wonton Soup." This is not your common wonton soup with thick skinned dumplings and unnaturally golden broth. This is a version of the Fujianese-style soup rarely seen beyond Chinatown's minuscule lunch counter Tai Jiang (a.k.a. "Chinese Restaurant"), with little pinches of meat in gossamer wrappers so translucent they look almost like little ghosts floating through the pale but flavorful pork bone broth, which has a subtle but distinctive hint of celery and scallions.

It is indeed a heartfelt homage to Sze's grandma, whom he knew as "Mama" and with whom he was close until she died two years ago: "It's considered peasant food, and a lot of my staff wondered why we'd put 'poor people's food' on the menu of a fancy restaurant. But I wanted to make one dish for my heritage."

It is so wonderful in its soulful simplicity that it really transcends its role as merely a nod to nostalgia. It's the heartfelt taste of a young chef born of hardworking immigrant parents who's processing his own American Dream in all its complexity with pride and ambition to make his own way. Yes, Tuna Bar is a worthy and upscale new addition to Old City's dining scene, with plenty of room to grow. But I'd go there regularly for a bowl of that soup every bit as much — and perhaps even more — than for any slice of Wagyu beef or toro tuna.