The main draw of Biao Ge, Cai adds, is the fish maw, a highly prized ingredient commonly used in Cantonese soups.

Fish maw is believed to be a good source of collagen, which helps one maintain a good complexion. It is also rich in phosphorus and calcium and is hence especially popular among women who are pregnant or who have just given birth. While fish maw is rather tasteless on its own, it does soak up the flavors of the broth well, resulting in a gelatinous texture that diners love.

"People used to associate fish maw with a luxurious delicacy that was exclusive to affluent families in the 1970s in Hong Kong. But a lot more people are able to enjoy it today because fish maw is becoming more affordable thanks to the greater availability of different fish as well as growing income levels," he says.