He asked his mother and aunts for cooking tips, studied online recipes, and watched TV cooking shows.

Whenever and wherever he ate something delicious, he would try to talk with the cooks to learn from them.

He cannot remember how and when he started hosting dinner parties for friends on weekends and holidays. Eventually, he started the business of a private kitchen, but not to make money, he says.

He charges 128 yuan ($21) per head, and says that price barely covers the ingredient cost.

"The private kitchen works in this way: I would learn how to cook better and how to run a restaurant, while customers would enjoy eating something special that they may not find somewhere else," Cheng explains.

On a recent visit with a colleague, I found the experience to be good value. When we sat down at the only dining table at his living room, we didn't know what to expect: Customers tell him their likes and dislikes while making the reservation, then Cheng decides on the courses, waiting to tell customers the menu as the dishes are presented on the table.

We started with a soup made with a small fish and bamboo chunks: The white soup was smooth and sweet, the fish was tender and fresh, and the bamboo tasted nutty.