"Hong Kong people strive for a perfect cup of milk tea like other people obsess about kopi luwak or Blue Mountain coffee," says Lai.
"We use a mixture of six types of Ceylon tea, four ounces of tea to a pot. Combined with Black and White brand milk, we can make eight cups of milk tea."
In the 1950s, Hainanese coffee was in fashion. Lum Muk Ho learnt to make the coffee and applied the technique to milk tea, selling it in his dai pai dong Lan Fong Yuen.
After making milk tea for decades, Lum passed his skills onto his son Lam Chun Chung. But even Lam has retired his sackcloth sieve now as his hands suffer from arthritis.
"Our customers in the past were vendors from Central market," says Lam. "Those vegetable sellers and fish mongers and even coolies, they would pass by our stall and see my father 'pulling' the tea through a sackcloth strainer, pouring it repeatedly from one container to another.
"The sackcloth would become stained and resembled a flesh colored stocking, so they would come in and say 'Give me a glass of that silk stocking milk tea.'"
The nickname for the drink stuck.
At Lan Fong Yuen, a very fine sackcloth and a copper teapot is used to make milk tea. The tea and milk are strained through the cloth sieve eight times to produce its incomparable velvet texture.
Try tasting the milk tea without sugar first to enjoy the richness of the tea aromas. Add sugar later on if you need it.