It was past midnight in a residential area in Cheung Sha Wan, and only Tai Po King Restaurant and a few other local eateries were still open on the quiet street. As I walked inside, loud chatter filled the small but bright dining area, and workers who’d just got off their night shifts were huddled around the tables clinking small glasses of beer and smoking cigarettes. Fresh chilli and spices were being fried in the kitchen, and the fumes started spreading out into the dining area. You could sense the anticipation as we all sat waiting for one thing: the restaurant’s signature Gai Bo (literally, ‘chicken pot’), a steaming pot of spicy, saucy, stir-fried chicken.

You could sense the anticipation

Hot pot has long been a big part of China and Hong Kong’s dining culture, a simple one-dish concept where fresh vegetables and raw meat are quickly poached in boiling soup stock, with soy sauce and condiments like fresh coriander, spring onions and garlic adding extra flavour. After all the ingredients are eaten, a belly-warming and nutritious broth remains. It is a shared dining experience, where families and friends gather around the hot pot to share stories and a meal.

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The versatile cooking method of hot pot is believed to date back to the early Middle Ages in the Asian steppes to the north as a solution to eat and keep warm around one communal fire, according to Mary Ellen Snodgrass in the Encyclopedia of Kitchen History. The centuries-old comfort food then spread around the region, inspiring variations like Szechuan Maotu hot pot, a Chongqing specialty with a tongue-numbing broth and cow innards; and Peking chrysanthemum hot pot found in Sukang, where the broth is made from white chrysanthemum flowers, prawns and pork. The cooking method even influenced Japan’s nabemono (table cookery) – a Japanese version of hot pot where the broth contains chicken or seaweed, and cooked ingredients are served in individual bowls with dipping condiments.

But the version that can be found today in Hong Kong is so comforting, flavourful and affordable that it has become a staple in a city that has a short attention span when it comes to food trends. It may not have been invented here, but with 266 restaurants offering Gai Bo on Hong Kong’s dining directory OpenRice, it has truly become a dish of the city.

It has truly become a dish of the city

What’s different about Gai Bo from traditional hot pot is its two-part process that effectively turns one meal into two consecutive ones.

First, a heavily flavoured pot of stir-fried chicken topped with a healthy handful of coriander is served on top of a gas stove to keep warm. Often diners will choose to add other ingredients like fish maw or deep-fried soy rolls to soak up the sauce. Then, once the chicken pieces are finished, broth or water is added to deglaze the pot, which turns the meal into a traditional hot pot. At this point, diners can order other raw hot pot ingredients to share; usual suspects include beef strips, prawns, pork balls and vegetables.

The dish’s huge popularity belies its relatively short history, and there is no consensus as to its exact origins. According to Edmund Lam, owner of Hong Kong’s Supreme Restaurant, Hong Kong’s first all-you-can-eat Gai Bo buffet chain, “It was first popularised in Shenzhen and mainland China, with flavours of Sichuan cuisine which are very spicy.” Indeed Yu Jun Restaurant in Shenzhen’s Xiangxi Village claimed to have invented it first in 1994, proudly proclaiming ‘The First Gai Bo’ on their menu.

Siu Chung Man, owner of Tai Po King Restaurant, believes that he was the first to bring Gai Bo to Hong Kong, in 2002. “It was the age of pork-bone hot pot, but we weren’t doing as well as the others. I remembered the Gai Bo we had in Xiangxi Village in Shenzhen and tried to make it for ourselves to taste. It was quite delicious, and so we starting selling it,” he said. “The sauce from Gai Bo is especially fragrant. It saved our restaurant and we see it as our saviour.”

Others like Lam and Jane Chin, owner of popular Jordan Gai Bo restaurant JKJ POT, say the dish pays tribute to ‘Jer Jer Chicken Pot’, a Cantonese dish traditionally served at dai pai dongs, or street hawkers, on roadsides in Hong Kong.

“Also known as ‘Chongqing’ chicken hot pot, [Gai Bo] is just a variation of the Hong Kong ‘Jer Jer Chicken Pot’,” Chin said. “There’s actually no Gai Bo in Chongqing. Hong Kong people gave it the name probably because its spiciness and taste resembles Chongqing’s spicy cuisine. There are less and less street hawkers in Hong Kong nowadays where Jer Jer Chicken Pot used to be very popular especially during winter, when people want to share a piping hot dish. Now, more and more young people go for Gai Bo instead for the similar feeling.”

Indeed, the cooking method of Gai Bo is similar to Jer Jer Chicken Pot – dry stir-fried. To get the heavy flavours to penetrate the meat, Gai Bo’s chicken is first marinated overnight in a spice blend that includes Sichuan peppercorn, star anise, cinnamon, angelica, soy sauce and oyster sauce. The marinated meat is then stir-fried in a wok before being served in a clay pot and garnished with fresh coriander. The name ‘jer jer’ is an onomatopoeia signifying ‘wok’s breath’ – the sound the raw meat makes when it hits the hot wok – and the irresistible charred aroma that results is a huge part of both dishes’ appeal.

“The trick is to wok-fry the raw chicken,” Chin said. “Some restaurants may first blanch the chicken to speed up the process, but that will result in white, bland and chewy meat that does not really blend well with the sauce.”

She explained that hitting the correct spice notes is vital, which is why she sources their Sichuan peppercorn and chilli directly from Chongqing, China – the source of Sichuan cuisine. These help create a sauce that is aromatic and spicy but doesn’t overpower the taste of the chicken.

Whatever the story behind the dish, today Gai Bo is ubiquitous throughout Hong Kong. Dedicated restaurants have popped up left and right over the last decade with varying recipes and concepts, from classic broths to luxury toppings. There were short-lived variations involving cheese, seafood and purple sweet potatoes, and what originally was just clear chicken broth can now be found as a lobster-based soup or a cocktail of Chinese herbs. A-la-carte Gai Bo restaurants in Hong Kong serve up premium ingredients like fresh seafood or hand-cut beef, but the true crowd-pleasers, with constant crowds of students and families, tend to be buffet-style, all-you-can-eat versions, where diners pay one price for unlimited amount of hot pot ingredients, as well as drinks and desserts.

Don’t skip the crispy soy rolls – they soak up the sauce to give you maximum flavour

Today, on any night of the week you’ll find Hong Kong locals huddled over a pot of Gai Bo, sharing stories, laughs and beers. Ultimately, everyone has different criteria for their favourite hot pot restaurant, be it the price, the sauce, the chicken or the location. However, if you're in Hong Kong in winter, Gai Bo, much like dim sum or pineapple bun, is definitely something you should make time to experience. My tip? Don’t skip the crispy soy rolls – they soak up the sauce to give you maximum flavour. A must-have at any Gai Bo table.

Culinary Roots is a series from BBC Travel connecting to the rare and local foods woven into a place’s heritage.

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