Lu attributes the brand's popularity to its fastidiousness in ensuring that each dish is freshly prepared.

Meanwhile, more youngsters have fallen in love with spicy food, which has become popular nationwide, he said.

Despite its popularity, the company does not offer delivery services as it wants customers to taste the freshly made food at its restaurants, he said.

It has also not opened any franchises as it would be hard to control the quality of food and service at such restaurants, he added.

Chef Fei's chili stir-fried pork has been ranked the top dish in Changsha, capital of Hunan, for six consecutive years, Lu said.

"We have the most certified master chefs of Hunan cuisine among all local restaurant brands."

The chili stir-fried pork is the top dish and a representative of Hunan cuisine, he said.

"We carefully select our ingredients. For chili stir-fried pork, we only use Kurobuta pork and make sure that only master chefs can cook the dish."

Despite the high cost of labor and ingredients, the company has managed to control the price of its dishes in first-tier cities. Customers on average spend just over 100 yuan at its restaurant for a meal, which is affordable for white-collar workers in big cities.

Meanwhile, the company has not raised funds from investors and is not seeking a public listing on the stock markets, Lu added.

"All of our stores are making profits, though not much, and we are not in a rush to expand rapidly," he said.

However, to cope with popular demand, the company plans to open dozens of new restaurants in Beijing, Shanghai, Guangzhou, Shenzhen, Suzhou, and Changsha. Its first venue in Hangzhou, Zhejiang province, will open on June 2.

In Changsha, its restaurants have also become a must-visit destination for travelers from all over the country.

Wang Bing, head of Chef Fei's restaurant at Huangxing Square in Changsha, said during the Labor Day holiday, National Day holiday and summer vacation, the eatery welcomes 2,000-3,000 customers every day.

About 90 percent of its customers order stir-fried pork with chili pepper, its signature dish. Meanwhile, to cope with strong demand, the store has extended its service time by one hour to 11 pm, he said.

Chen Jie, 26, traveled to Changsha from Beijing recently with friends and tried out one of Chef Fei's restaurants in the city.

"It is very famous and the waiting time in Beijing is too long, so I told myself I must try it out in Changsha," he said.

It is not too spicy and perfect for someone from northern China who wants to try spicy food but is unable to tolerate the strong flavor, he said.

Xie Jiahui and her friend went to Chef Fei's restaurant in Changsha before heading back home to Shaanxi province.

It was the second time that they were visiting Changsha and having a meal at the restaurant. "I like the city and its food very much and I find local people are very happy and lead relaxed lives," she said.

Lu, the PR manager of Chef Fei, said although Hunan cuisine has been well-received in the country, there has not been a well-known brand representing its local cuisine. "We want to make the brand recognized nationwide. We are making progress in bringing Hunan cuisine to more people, so they can experience its appeal."