Green rice balls are available all year round, but their demand spikes a few weeks ahead of the annual Qingming Festival. photo by gao erqiang / china daily

But Liu, a former pastry chef, said that making the perfect rice ball requires little skill. Instead, it is all about finding the right ingredient — wild mugwort. At Wang JiaSha, the chefs only use wild mugwort from Ningbo, Zhejiang province.

In contrast, many food factories and snack shops use a powdered form of the plant instead. This practice is believed to have originated in northern China because the low rainfall in that region during the start of spring means that the plant is not “juicy” enough for use. Furthermore, using the powder speeds up the process and in turn results in the products having a longer shelf life.

“We are one of the few that use fresh mugwort to make the rice ball. The unique aroma it provides is what makes customers come back for more,” said Liu.

When the restaurant opens at 7 am, the queue to buy the rice balls at Wang JiaSha usually measures more than 100 meters. In line are people of all ages, and Liu noted that the rice ball has in recent times grown in popularity among the younger generation.

One of those in the queue was a 56-year-old Shanghainese woman surnamed Zhao, who said she was buying the rice balls for her son and not as offerings for Qingming Festival.

“This restaurant is my son’s favorite when it comes to this snack. Our ancestors aren’t picky like my son — they will make do with those from the supermarkets or other shops. Besides, they can buy whatever they want with the hell money we burn for them,” joked Zhao.

xujunqian@chinadaily.com.cn