Mabel's clay pot chicken is among the main courses that the twin sisters cooked for Premier Li Keqiang. Photo provided to China Daily

A serious mind behind Premier

US first lady visits China

"He said he wanted something unique for Premier Li," Lisa says.

Mabel's clay pot chicken, a dish named after the sisters' mother, won Sweet Mandarin the title of Best Local Chinese Restaurant in the UK on the television show, Gordon Ramsay's F Word. Their dishes are family recipes that have been handed down from generations, she says.

Part of the meal also featured their homemade sriracha sauce, one of their best-selling sauces which have become so popular that Lisa has secured a deal to sell them directly in China.

However, cooking for Cameron was not all smooth sailing. "When we first arrived at 10 Downing Street we could not get in as we were not on the guest list and eventually Cameron's aide had to let us in," Lisa recalls. And then, the kitchen stove needed to be fixed as it wasn't working. After all that Lisa says, "I imagined I was back at Sweet Mandarin and cooked my heart out".

Lisa finds China "an amazing and a very diverse place which is steeped in culture, history and beauty and is a treasure trove of opportunities". The twins love China, Lisa says. They hope to have a TV show in China someday when they can show Chinese people where to visit and eat in Britain.

Lisa and Helen are from the fourth generation of a family that has been cooking Chinese food and making sauces. "We grew up in a family firm that was built on decades of hard-earned experience, and we were expected to give up our evenings and weekends to help out behind the counter or in the kitchen," Helen says.

While Helen trained to be a lawyer and Lisa a financier, they ultimately followed on the family's path and together launched Sweet Mandarin in 2004.

Helen's book - Sweet Mandarin - published by top British publisher Random House in 2007, and distributed across 33 countries, documents how Chinese people emigrated from China to the UK.

Zhou Heran contributed to this story.