Chongqing hotpot uses beef tallow, large quantities of chili and Sichuan pepper.[Photo by Tang Yingzi/China Daily]

During World War II, when Chongqing became the wartime capital, the dish gained popularity with people from all around the world.

Chongqing hotpot uses beef tallow, large quantities of chili and Sichuan pepper. The three must-have varieties are ox stomach, duck intestine and large artery of pig or ox.

As competition is fierce, there are many outstanding outlets in the city and locals can never agree on which one is the best. Everyone has his or her ranking list.

In Chongqing, a less-than-glamorous hotpot shop called "Big Dragon", down an alley in Shapingba District, is the go-to place for real foodies. It opened at least 20 years ago and it has never changed. Though there are so many knockoffs in Chongqing and other cities, the owner has no ambition to open more outlets.

The shop is always crowded, even at midnight, and has a long queue during peak hours. The dishes are fresh and reasonably priced, service is quick and considerate, but the secret is its soup base and homemade chili pepper sauce.