It’s a common Chinese custom, where locals make their own food, and often use the same ingredients to make it as it was made in the country, including the fish, rice, beans and chicken.

But with a new startup called Sunnysider, the idea is to give locals a place to get their fix of Chinese food without the high price tag and the inconvenience of long waits.

And its been a hit.

A week after opening its doors in Shanghai on December 3, Sunniesider says it’s now the largest Chinese restaurant chain in China, and the largest in the world.

It’s a huge success story, says Sunnowsider founder and CEO Huang Zhenli.

Its business model is based on a single ingredient: the word “shenzhen”.

“When you look at Chinese food, we want to offer people Chinese food at the same price that you would pay in Hong Kong,” Huang says.

“That is a unique opportunity to get more Chinese food in Hong kong.”

But the idea has also attracted the ire of the Chinese government, which considers foreign companies that offer services to Chinese citizens as illegal.

“If a company like Sunnucksider wants to come in and serve food to Hong Kong, then they need to register with the Chinese authorities,” says a Hong Kong-based official who wished to remain anonymous.

Sunnysiders founder Huang has been trying to get his business to register, but says he’s still waiting for an official response.

And he’s been a little frustrated by the Chinese officials’ response to Sunnisons challenges.

“We have had to give up the trademark and license to the word Shenzhen in order to get our restaurant registered, and they have rejected it,” Huang told ABC News.

But he says his business model isn’t based on trademark, so why should he be penalised for it?

“Our business model doesn’t require the trademark.

We’re simply selling the product to the customers.

If we’re in Hongkong, we can sell the product here,” he says.

Sunnsider’s Shanghai cafe opened last week and has so far been hit by some of the most intense scrutiny of the new Chinese food trend.

“It’s been extremely challenging.

I can’t tell you how many people have called to complain,” Huang said.

Sunny food with a good service is a huge challenge for the Chinese Government, says the official.

But Huang says that it’s also a huge opportunity for his company, as it’s been able to sell its product in a market that has seen a number of food riots.

“There are people who are willing to pay more money for Chinese food because it’s better,” Huang explains.

Sunniysider started out in Shanghai, but moved to Guangzhou last year to expand its operations.

And now, it has more than 1,500 outlets in Hong-Kong, Shanghai, Guangzhou and Guangdong.

“The market in Hong Kong has been completely dominated by Chinese companies,” Huang added.

But now, Sunnsider is looking to expand to other parts of China.