Hotpot, stolid fare in the UK, is an interactive food phenomenon in China. Hotpot restaurants there combine sociable feasting with customer participation. Diners can hand pick every ingredient, down to the number of clams in the boiling soup that cooks them. Customised sauces and salad bar are included. Rising profits from China’s largest chain, Haidilao, are the sweet desserts for investors. In future, robots may dish these up.

Hotpot fans say the lip-numbingly spicy Sichuan chilli soup is especially addictive. Such menu must-haves helped spending on hotpot meals to outpace disposable income growth in China last year. Around 14 per cent of an annual dining-out spend of $600bn goes on hotpots. The market has expanded at a rate of more than 11 per cent over five years. Haidilao restaurants have opened at almost twice that pace. 

Even at this rate of growth, the market is far from saturated. Haidilao has just a 2 per cent share of the dining market. The top five together have less than a 10th. For Haidilao, that 2 per cent served up $2.5bn of revenue last year. Profits are helped by labour costs that are up to a third lower than for other restaurant chains, including for fast food. Fewer waiters and chefs are needed when customers assemble their own hotpots.