A picture shows Oguzhan Sayi is cooking kokorec in his restaurant in Istanbul, Turkey on Oct. 5, 2018. (Xinhua/He Canling)

ISTANBUL, Oct. 9 (Xinhua) -- A Turkish man and his wife were working feverishly at a small and stylish restaurant parallel to Istanbul's bustling Istiklal Avenue, as lunchtime was nearing.

Oguzhan Sayi, the 32-year-old owner of the eatery named Ozzie's since 1968, was lining lamb intestines on a horizontal skewer over charcoal fire, while his wife was setting the tables.

"This place will be soon jam-packed with customers, mostly working people, who rush here during their break time in the middle of their busy days," Sayi told Xinhua.

To his first customers of the day, he served two portions of kokorec, a local street food delicacy made basically from lamb intestines, which are wrapped around sweetbreads on skewers and grilled horizontally.

He chopped the grilled intestines, sprinkled it with cumin, oregano and salt, and put them inside a loaf of bread.

Sayi has been in the business for only two and a half years, but he is well known now in the country for his kokorec.

Unlike his grandfather, who learned how to cook tasty kokorec from Albanian masters, and his father, Sayi had no interest in running a kokorec restaurant until 2016.

Instead, he went to a health college to be trained as a surgical technician.

After his father died, the family's small restaurant, which was then located in Dolapdere, a notorious Istanbul neighborhood known as home to drug dealers and criminal gangs, remained closed for a long time.

"After resisting the idea, I was finally convinced to run the business and take the ancestral knowledge transmitted from my grandfather," he said.

The sales, however, were not as expectation at the beginning. In frustration, Sayi sometimes went out to deliver orders.

"Then I started to open booths at various festivals and got more and more recognition," he said, adding that "I once thought that I was going to close the business in two or three months, but here I am."

Now, Sayi's customers include celebrities, artists, columnists, writers and politicians. He even gets orders from abroad, including the Netherlands, France, Canada and Gulf countries.

He does not accept any costumers in his eatery without reservation.

Despite such popularity and calls for branches opened both across the country and abroad, he is against the expansion.

"I have no intention to let others use my name," he said, adding that he even does not hire any waiter.

For Sayi, kokorec is best made from young lamb.

Lamb is expensive and it is difficult to find lamb's intestines in the country. One kilogram of lamb intestine costs 250 Turkish liras (40 U.S. dollars).

"Consequently, other kokorec cooks mostly use the intestines of any animals they can find in the market," said Sayi, noting that "it leaves a strange, dull taste in your mouth."

"I prepared it in a specific way so that its taste in your mouth changes as you chew it," Sayi explained.

According to him, kokorec carries numerous beneficial bacteria which are helpful in strengthening the immune system.

In a showcase at the entrance to his restaurant, Sayi displays a 100-year-old kokorec wheeled cart that once belonged to a Macedonian cook.

"It takes six hours to cook kokorec on it," Sayi said, noting its taste would be even more delicious when cooked for long hours.

Ismail Kilic, police chief of the Beyoglu district, is one of Sayi's frequent costumers.

"Our friend here is doing an incredibly delicious kokorec," Kilic said.

"When I took the first bite, I realized that I just wanted to eat my kokorec in silence, focusing solely on the taste in my mouth," another customer from Turkey's western province of Balikesir said.