'Silk stocking' milk tea is a misnomer. The elongated bag that chefs at Lan Fong Yuen use to filter milk tea is made of thin cotton. 'When my father first served the drink, customers saw the tea-stained bags and thought they looked like the colour of the silk stockings that women wore,' said Lum Chun-yip, whose father started the trend about six decades ago. 'But if it were silk, the bags would melt under the heat of the milk tea.' Mr Lum said that in the 1950s, most Hongkongers drank coffee. But his father, who arrived in Hong Kong from Chaozhou in the 1940s as an apprentice chef, felt caffeine was too much of a stimulant and wanted to serve a milder drink. He started to experiment with milk tea. 'Once, some sailors came to see my father with a bag of tea leaves from Sri Lanka. They told him it was good stuff and asked him to try,' Mr Lum said. The elder Mr Lum created a milk tea by combining six types of Sri Lankan tea leaves - one of Lan Fong Yuen's secret recipes. He found the texture of the tea could be made smoother by removing the residue with a cotton filter.