Matteo Catalani partnered with his uncle Daniele to sell fresh pastas and prepared foods at Cucina Al Volo, a stall in Union Market. (Dixie D. Vereen/For The Washington Post)

Matteo Catalani rattles off cooking instructions like a doctor prescribing medicine. It’s a Sunday afternoon at Union Market in Northeast, where Catalani operates a fresh pasta stand called Cucina Al Volo. The name means “kitchen on the fly” in Italian, appropriate considering its co-owner hardly stands still. He scrubs skillets. He plunges tongs into a pot of boiling water, loosening bundles of fettuccine as puffs of steam vanish into his dark locks, tied neatly into a bun.

He dishes constant advice about pasta. Sometimes people don’t even have to ask.

“Boil water. A pinch of salt. No more than three minutes,” Catalani says as he sells an uncooked batch to a customer.

How long will it stay fresh? “Five to six days.”

What about the pesto? “As long as it’s coated with oil, it’ll keep.”

Years ago, while living in Italy, he never imagined he would wind up cooking pasta in a place that also sells kolaches and Korean tacos. Catalani, 23, harks from a city near Florence called Pistoia. He’s proud of his provenance: For evidence, look no further than the tricolor flag stitched onto his uniform. He focused on chemistry and biology in high school before realizing he didn’t see a future for himself in science. In 2011, he left Italy for Washington to join his uncle, Daniele Catalani, a chef here since the late 1990s, formerly of Galileo and Toscana Cafe.

Tired of the restaurant industry’s crowds and chaos, the duo launched a new venture focused on what they enjoy most: pasta. They carved a niche for themselves by selling fresh noodles directly to home cooks. Now Matteo is handing over fresh pappardelle to customers with the care of a parent delivering a newborn to a sitter. “There’s a lot of demand for good food, but there’s not a lot of people providing it,” Matteo says of Washington. “We have a purpose here.”

Besides Union Market, the two pop up at the Bloomingdale and the 14th and U farmers markets May through November. But as their tiny operation soars, they face a conundrum: Can they make it big without losing their small-time charm?

Matteo likens his work to a lot of things. It’s cookery, yes, but it’s also a form of consulting. Customers turn to him when they have pasta-related problems: What should they cook at a dinner party for five? “People come to me without knowing what they want. I talk to them, establish a relationship with them and help them out,” he says. “This is what I love.”

Matteo Catalani makes fresh egg fettucine at Cucina Al Volo in Union Market. (Dixie D. Vereen/For The Washington Post)

Matteo Catalani cooks fettucine and duck ragu, which is Cucina Al Volo’s best-selling sauce. (Dixie D. Vereen/For The Washington Post)

He’s a hit with crowds of all ages. He cooks buttered noodles for the birthday girl in a pink dress, even though the dish isn’t on the menu. He gives a discount to the dad who returns a canvas tote’s worth of empty sauce jars. And he’s polite, imbuing regular conversations with the formality of “Hello, sir,” and “Yes, ma’am.”

Most of Catalani’s prep work occurs at Union Kitchen, a shared production space populated by food start-ups such as Compass Coffee. There, he layers tomato sauce, braised short ribs, fresh pasta and bechamel into lasagna and cooks a variety of sauces — duck ragu, lobster and shrimp, wild mushroom, eggplant-tomato, pesto — to sell alongside his pastas. He clings to tradition and makes squid-ink fettuccine and kale-spinach fusilli. Other times, he breaks loose, creating offbeat recipes such as smoked paprika pappardelle.

On Mondays and Tuesdays, he works from about 7 a.m. to 1:30 a.m. in the kitchen, prepping sauces, doing inventory and making orders. “He works hard all day long,” says Jason Rosen, a frequent customer. “He makes sure everything is consistent.”

Catalani doesn’t usually shape pasta at Union Kitchen. Instead, he transports the vibrant doughs to his cramped market stand, where he stuffs them into a bronze-plated pasta machine that pumps out ribbons of black, orange and green. He cranks the handle on an old-school pasta maker to shape his ricotta cavatelli and seals every single raviolo by hand.

He built a clear barrier around his prep area, so wide-eyed customers can gawk at the pasta as it emerges from the machines, a sight he says can be hypnotic. He stacks the finished bundles on drying racks, which he assembled himself using materials from Home Depot. “I never saw anyone selling it,” he says. “So I make it myself.”

Cucina Al Volo sold only uncooked pasta until customers asked Catalani to serve it cooked with his premade sauces. The decision has paid off. Cooked pasta sales have nearly matched sales of the uncooked variety. On Valentine’s Day, he sold more than 100 pounds of both.

“People come to me without knowing what they want. I talk to them, establish a relationship with them and help them out,” says Matteo Catalani. (Dixie D. Vereen/For The Washington Post)

Restaurants have asked to carry Cucina Al Volo’s products. But the owners feel the company is too young for such large commitments. “You stretch too thin, and you start cutting corners,” Daniele says.

That sort of conviction doesn’t come cheap. A jar of pesto at Cucina Al Volo costs $11. A pound of fresh pasta goes for $8.

People are willing to pay for it, though, and apparently so are investors. A group of potential backers has approached the Catalanis about setting up a casual restaurant downtown, potentially equipped with an open kitchen and salad and gelato bars. The concept could work for the pair, as long as it doesn’t involve too many complications. “We just want to make good pasta, not to go too crazy,” Daniele says.

In the meantime, Matteo wants to host cooking classes and keep on doing what he’s been doing: making pasta and hopefully helping some people along the way. “It’s kind of a therapy,” he says.

Daniele agrees: “Whenever my wife and I have a fight, I go and make pasta. When I come home, I say, ‘Hey, try this,’ and we make peace.”

Cucina Al Volo, 1309 Fifth St. NE.