Often referred to as shrimp bonnets due to their unique shape, har gau are arguably the most popular dim sum dish of all. Plump and meaty with translucent pleated skins, the steamed dumplings are so complicated to get exactly right that they are often the dish that the skill of a dim sum chef is judged on: the wheat starch dough must be pliable and opaque yet robust enough not to break when picked up with chopsticks; the generous filling inside should be moist but not rubbery, as is common when cooking prawns; the dumplings mustn’t stick to the steamer basket or to each other; and they must be able to be eaten in one bite.
It is commonly believed that har gau were created at the beginning of the 19th century by the owner of a small teahouse in Guangzhou, the capital of Guangdong Province. In a town fraught with competition, the teahouse owner decided to take advantage of the plentiful seafood available on the Pearl River or Zhu Jiang, the river that runs through both Vietnam and China. He purchased prawns sold by fisherman directly from their boats and added pork and fresh bamboo shoots before wrapping it in a delicate dumpling skin, creating the har gau that is so widely associated with dim sum today.
The beauty of har gau dumplings lies in their simplicity: aside from the dough, the dumplings contain very few ingredients. Prawns are the only vital component; anything else is just added extra, although traditional har gau also contain pork (or pork fat) and bamboo shoots. Seasonings such as salt and sugar are added to Yauatcha’s har gau to give it depth and a slight sweetness that brings out the flavour of the simple dumpling. Nothing more or less is needed.
Note: this will make enough pastry for approximately 100 har gau dumplings. Attempting to make a smaller amount will make it difficult to achieve the correct consistency of the dough.
Submerge 9kg of fat, meaty prawns in cold water for around 30 minutes. This ensures that the prawns will taste crisp and firm. Drain the prawns properly and then chop to a fine consistency in a food processor (or by hand). Add your seasonings: half a tablespoon of potato starch, half a teaspoon of ground white pepper, one tablespoon of salt, two of sugar and 420ml of vegetable oil.
Freeze for two to three hours. The prawn mixture will solidify, making it easier to wrap the har gau.
While the prawns are freezing, make the dough. Sift 600g potato starch and 600g wheat flour into a large bowl. Slowly pour a litre of hot water into the bowl whilst stirring the gradually thickening flours with a palette knife or a wooden spoon. Once the dough has come together, lightly knead until it becomes a smooth ball of pastry.
Lightly flour the surface. Separate the pastry dough into small round balls.
To make the har gau, roll one pastry skin out until it is 6mm thick. Place the pastry skin in the palm of the hand and spoon one tablespoon of the prawn filling into the centre. Using the index finger and thumb, mould the pastry skin upwards around the filling and pinch it together into a shell shape.
Place the har gau into a dim sum steamer basket and steam for approximately three and a half minutes. Serve piping hot.