From finishing every grain of rice in the bowl to knocking on the table, these etiquettes have been passed down through generations and can be traced all the way back to ancient China.

As a born and bred Hong-Konger, going to yum cha with my family every Sunday is an important tradition that has lasted many generations. Here, stories old and new are recounted over a table full of bamboo baskets that hold a variety of dim sum – small bites that encompass everything from delicately translucent prawn dumplings and silky rice rolls to molten lava custard buns and sweet roasted pork buns.

Literally meaning ‘drink tea’ in Cantonese, yum cha is as common a meal in Hong Kong as coffee and toast in Western culture, where Chinese tea is enjoyed with dim sum at traditional tea houses. Dating back to ancient China, teahouses have long been a place of rest and conversations for the common people.

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After World War Two, new immigrants from China brought yum cha culture with them, often becoming a regular routine between family and friends, and still now it remains an important part of Hong Kong society. Though it is a Cantonese cuisine originating from China’s Guangdong province, Hong Kong remains one of the best places in the world for authentic yum cha food and atmosphere.

Yum cha is a group activity that involves everyone around the table. As it’s centred on sharing, there are certain things to bear in mind when you’re being served or serving others. My grandmother, the eldest in our weekly yum cha gathering, has always been quick to straighten out everyone’s table manners. A few rules that she frequently mentions include finishing the last grain of rice in the bowl so a future spouse’s skin will resemble the smoothness of the clean bowl; and to never stick chopsticks straight down into a bowl of rice because it resembles incense for the dead and will bring bad luck. She also reminds us to never bang our chopsticks on the bowl for fun because that was what beggars used to do for attention and is thus believed to bring poverty to the family.

To the uninitiated, these rules may seem random. But they are etiquettes that have been passed down from one generation to another through anecdotes that trace all the way back to ancient China.

One of my favourite examples relates to flying elephants. In Chinese chess, or Xiangqi, the two opposing sides are divided by a river, and the goal of the game is to move across the board and capture your opponent’s king piece. As a rule, the pieces labelled elephant or xiang play a defensive role and are not allowed to cross the river into the opponent’s side.

Just like the elephants in Chinese chess, I was taught from a young age that at the yum cha table you are not supposed to ‘cross the river’ and go beyond your reach for dishes that are placed further away or in front of someone sitting opposite you. It is considered rude and undesirable behaviour at the table. Instead you should wait until the dish is placed in front of you or ask someone to pass it. That is also why, whenever I did occasionally forget the rule, my grandmother would tell me not to ‘飛象過河’, the neat four words that describe an elephant flying across the river and a reminder to stay within my reach.

While my family and I enjoy a few rounds of dim sum and catch up on stories from the past week, Chinese tea makes for the perfect drink to sip on and help cut through the oiliness of the food. To begin every meal, the task falls on me, the younger generation, to order and serve the Pu-erh tea my family likes, then make sure everybody’s cups are filled throughout the meal. My grandmother, who has spent many years working at a local teahouse, will knock on the table as a way of signalling thanks to the person who poured her drink. And the story behind this is one that many locals, including myself, will have heard many times before.

According to legend, Emperor Qianlong of the Qing dynasty once visited a town in China dressed as a civilian, accompanied by several staff as security. The group decided to go to a teahouse to yum cha, and the emperor took a teapot and poured his staff some tea. The staff were terrified, but could not kneel to thank the emperor for fear of breaking his cover. Instead, they had a lightbulb moment, and knocked on the table three times with three fingers curled to signify kneeling three times as gratitude.

Since then, the ritual has been well noted in modern literature, such as in Kung Fu Tea Dialogue (功夫茶話) by Cao Peng, as a way to thank someone during yum cha without interrupting the conversation or talking with a full mouth. Cao also noted that the gesture means both saying yes to more tea, as well as gratitude.

Unfortunately, the possibility of this story being historically accurate is rather low, according Dr Siu Yan-ho, a lecturer in the Department of Chinese at Hong Kong’s Lingnan University.

“The chance of the Qianlong Emperor visiting the society in civilian clothing was not high. The official diary of the emperor, as well as other related historic records in the era, are considered very well preserved, but there is currently no record of him doing such a thing,” he explained.

However, an alternative source for the tradition comes from Xu Jie-Xun in his book Han Dynasty’s Folk Customs (汉族民间风俗). He explains that during banquets in the Tang and Song Dynasties, guests had to sing a song for each round of drinks while the listeners created a beat for the singer. Without proper percussion instruments on hand, people would instead knock their fingers on the table, known in Chinese as ji-jie (擊節). Although the custom of singing at banquets has faded away, knocking on wood has become a sign of thanks and encouragement used now solely for tea-pouring. The meaning of the Chinese term ji-jie also transformed from ‘creating a beat’ into ‘knocking on the table’.

There are different ways to knock, depending on your relationship with the person pouring the tea. To elders, you should knock with a closed fist, to symbolise prostration and admiration. Between people of the same generation, knock with your index and middle fingers, much like cupping one fist as a sign of respect. Towards younger people, as my grandmother would do to me, just a single finger rap is needed as a nod of thanks.

We drink so much tea that we usually need to refill the single teapot on the table every half hour or so. Whenever we need the wait staff to top up the pots with hot water, we know to leave the lid of the teapot open and the lid balanced on the handle as a cue. This move is done for the wait staff’s sake, so they don’t have to check on the pots or be waved down – but what started this is said to be far more than just convenience.

According to Siu, the origin legend has been long passed down through Chinese families as a fun anecdote. “The story goes, back in the late Qing Dynasty, there was a man who was the nephew of a powerful palace, and who was often avoided by civilians in fear of being bullied,” Siu explained. “One day, he went to a teahouse after a big loss at the bird-fighting ring, and decided to set up a scam to get his money back. He took an empty tea pot and placed his bird into it. The waiter came to fill up the pot, but once he opened the lid, the bird escaped and flew away. The man then began to throw a fit, demanding compensation. Luckily, a martial arts master intervened and dissolved the situation, but ever since that day, the teahouse owner made a rule that customers must open the teapot lid to show that it needs filling up.”

Another version was told to me by Mr Lam, who works at iconic teahouse Lin Heung Kui in Sheung Wan, in which the scalding tea killed the rich man’s bird in the tea pot, hence the rule to avoid future compensation. Thus began this tradition of a silent symbol, gladly adopted by the industry and diners alike, and passed down through generations for the sake of first transparency, then efficiency.

Nowadays, hot water in insulated pots is usually available on each table so that diners can top up the tea pots themselves. But even now during our weekly yum cha sessions, my family will still leave the lid balanced on the handle of an empty tea pot, even as we refill the tea pot ourselves, and continue to teach younger family members the stories behind the table manners and rules.

So next time you’re heading to yum cha in Hong Kong, be sure to knock on wood as a sign of thanks to the tea-pourer, think of the flying elephant before reaching for food, and ask a local about the many fun tales of Chinese table manners.

The Ritual of Eating is a BBC Travel series that explores interesting culinary rituals and food etiquette around the world.

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