With his flowing black hair, bushy beard and slight paunch, Behroush Sharifi hops off his bicycle and bounds into an expensive restaurant on the Upper West Side.

He takes the leather satchel hanging from his shoulder and starts to pull out little baggies packed with exotic spices, displaying them on a steel counter for chef John Fraser to examine.

“That’s amazing” Mr. Fraser says as he tastes some ground sour grape. “We’ll take this. Leave the whole bag. I’m serious. I’ll buy it.”

Such reactions aren’t unusual when Mr. Sharifi — aka the “Saffron King” — peddles his wares to the city’s most famous restaurants such as Babbo, Daniel, and Jean Georges.

For the past six years, Mr. Sharifi has quietly filled a crucial niche in Manhattan, helping chefs complete intricate menus with his coveted spices.

But Mr. Sharifi is more than just a salesman. He’s a throwback to a time in New York when chefs never bought products from vendors until they had a chance to touch, feel, and taste them. Along the way, he has become indispensable for many chefs.

“There is only probably a handful of people who come to you, and he’s definitely the best of them,” Mr. Fraser said.

Mr. Sharifi’s spice route stretches from China to Turkey. His exotic inventory includes Aleppo pepper from Syria, Indian pine nuts called Chalgozeh, and Lebanese red hibiscus, among many others.

The erudite and gregarious Mr. Sharifi, who came to America in 1981 after spending time in England, never intended to get into the spice business.

It just sort of happened. While he was studying for his master’s degree in New York City, Mr. Sharifi focused on mystical Iranian poetry. He found food-related passages dotted with saffron references.

Saffron dates back more than 3,000 years and was originally used as a dye and not in dishes. Cleopatra was said to put it in her baths, so did Nero in Rome; some have suggested it’s an aphrodisiac. “The word saffron is imbued in Persian poetry,” Mr. Sharifi said. “It’s not just a culinary ingredient.”

It’s also a commodity. And Sharifi realized that if he tapped his Iranian connections — mainly his family — he could sell it. But there was a hitch. The U.S. had a trade embargo against Iran.

When sanctions against Iran were finally eased in 1999 — allowing the sale of food and medicine — Mr. Sharifi soon went into business.

He bought the domain name SaffronKing.com and began figuring how he was going to import the spice. He turned to his family in Iran, relying on his cousins and their resourcefulness.

“Logistically it’s a nightmare,” he said. “Bribes aren’t unusual.”

Mr. Sharifi says he managed to get his first shipment of 220 pounds of saffron about six years ago from eastern Iran.

Since then, he has slowly established a rapport with chefs who buy the saffron for as much as $88 an ounce.

Chefs say it’s worth the steep price.

“It was not like any saffron I had ever seen before,” WD-50 chef Wylie Dufresne said. “It was fantastic.”

Mr. Sharifi lists more than 250 restaurants as clients in Manhattan.

While he has increased his spices, not much has changed in the way he runs his business. His apartment on the Upper West Side is still stocked with his wares. And he still uses his bicycle to get around the city.

In a single day, Mr. Sharifi can hit two dozen restaurants. His methods are effective. There is no song or dance. He just shows up and lays out his goodies.

Chefs take notice.

Recently, Mr. Sharifi rolled into the three-star Picholine near Lincoln Center. He was instantly recognized.

“Hey Behroush,” shouted a sous chef, Carmine DiGiovanni.

Mr. Sharifi got down to business with Richard Farnabe, the new chef de cuisine. Mr. Farnabe, who has cooked at New York restaurants including Jean Georges and Daniel, knew Mr. Sharifi from previous cooking gigs.

Inside the kitchen, Mr. Sharifi explained his newest spices. He discussed the uses and history of manna, which is the resin from wild-growing bushes in the deserts of Iran. It has the look and feel of rock candy.

He showed Mr. Farnabe dried ginger, white figs, green cardamom, white mulberry, sour plums, and fennel seed from India.

Finally, Mr. Sharifi pulled out his saffron cotton candy, his ace in the hole. Mr. Farnabe sampled it. “Very good,” he said while shaking his head. “Very, very good.”

After a few minutes, Mr. Sharifi had another customer.

“We are back in business,” Mr. Farnabe said.

A happy and sweaty Mr. Sharifi thanked the chef, walked outside, and unlocked his bike.