Khoa Nguyen’s grandmother would not understand everything about his new restaurant, Ba Bay. The industrial, polished concrete floors might perplex her, and so might the Arcade Fire tunes playing in the dining room or the mohawked young host waiting at the door. Still, she likely would find plenty of familiar comfort food on the menu.

Nguyen named his modern Vietnamese establishment (633 Pennsylvania Ave. SE) after his nonagenarian grandmother: “Ba Bay” translates loosely to “Madam Seven,” an affectionate name for his grandmother that refers to her late husband, who was the seventh child in his family.

In this hip, spare dining room, chef Nick Sharpe has paired traditional dishes with modern riffs on Vietnamese flavors. Sharpe’s pedigree, which includes stints at nearby Sonoma and the now-defunct Maestro, and the restaurant’s stylish, contemporary vibe, set Ba Bay apart from many of D.C.’s tchotchke-filled ethnic restaurants. 

Nguyen, 31, who worked for five years as a manager at Vidalia, says diners are sometimes thrown by the ambiance or by the modern twists on Vietnamese classics. “People will say, ‘Wait, that’s not how it’s supposed to be!’ and we say, ‘Well, it’s not traditional, but let us take you on this journey.’” 

That trip might take diners to a plate of shaky beef, rosy slices on a slick of watercress puree, brightened with the vinegary tang of pickled red onions. Or a deep bowl of rich pork broth and noodles that would scare off the worst head cold. Spoonfuls from the bottom of the deep bowl might dredge up a sliver of pork loin or rich pork shank. 

Bahn mi, the famously addictive Vietnamese sandwich, is available only at lunch. A crisp baguette gets a slather of house-made pate (all charcuterie is made in-house) and a rotating variety of fillings, perhaps braised short rib one day or fiery chicken another. 

Nguyen, who was born in Saigon, moved with his family to Hampton Roads, Va., when he was 11. Initially, he planned to open a modest eatery offering bahn mi and other street foods.

But when he began assembling his team — including Sharpe, with whom he had worked at Vidalia, sous chef Sara Siegel (whose previous stints have included the famed Babbo in New York) and manager Ken Tu — the vision evolved into something grander. 

First came finding the right space. His broker called with a lead: The space that had housed the short-lived Locanda restaurant on Capitol Hill was available. 

After a few months giving the restaurant a face-lift — removing ugly sound-muffling panels and hanging pendant lights with Edison-style bulbs and shades made of traditional Vietnamese baskets — Nguyen opened the doors in mid-November.

And as the interior was being readied, Sharpe made preparations of his own. The accomplished chef had eaten his first Vietnamese food only a year earlier. “When Khoa asked if I was interested, I told him yes, as long as he understood that I had no idea what I was doing,” Sharpe says. 

His crash course included plenty of meals with Nguyen at Vietnamese joints, many in the Eden Center in Falls Church, Va., and some as far afield as Richmond, Va., and New York. But the ultimate training came during a three-day visit that the two men made to the home of Nguyen’s parents in Williamsburg, Va. 

Nguyen’s mother, along with assorted aunts and family friends, gathered for an epic stretch of cooking and eating that indoctrinated the young chef in the foods of their homeland. The two describe the mini boot camp as a glutton’s dream: Cooking started in the morning, with a break for a hearty lunch, followed by more cooking and a long dinner, followed by desserts, card games and plenty of bourbon. 

Pho-making wasn’t the only skill that Sharpe picked up. “I learned Vietnamese black jack, which has like a thousand rules, and I’m pretty sure they were all cheating,” he says. “There may have been drunken palm-reading.” 

Since opening, the restaurant staffers has found their Capitol Hill neighbors welcoming. They are addicted to coffee from Peregrine, the cafe near Eastern Market, and the baristas there return the patronage. The Ba Bay crew has adapted to the Hill’s clientele, which Sharpe calls “wildly eclectic.” The lunch crowd includes plenty of Hill staffers; at dinner, the young families and older couples come in early.

Plans for the future, Nguyen says, include creating an enticing Restaurant Week menu and, perhaps most importantly, finally getting a sign out front to alert passers-by to the dining experience that awaits inside.

The new sign will incorporate the restaurant’s logo, a daunting meat cleaver inside a circle. Nguyen says, with an impish smile, that among older Vietnamese, pictures of knives are considered bad luck. 

He clearly doesn’t share his elders’ superstition. Despite its name, this isn’t his grandmother’s restaurant.