Lisa Tse (right) and Helen Tse at 10 Downing Street. Provided to China Daily

Mabel's clay pot chicken, a dish named after the sisters' mother, won a television competition to be named a Gordon Ramsay's Best Local Chinese Restaurant in the UK, beating 10,000 other restaurants for this award.

Lisa Tse also says Mabel's clay pot chicken is inspired by her mother's favorite dish. "Our mother, Mabel, remarked that she lost her childhood innocence when she arrived in England in 1959. Her mother, Lily, had left her and her brother Arthur in Hong Kong for three years whilst Lily carved out her business in the UK. When Lily brought Mabel, aged 9, and Arthur, aged 12, to England, Mabel missed the sunshine, her friends, the good food and most of all her grandmother."

It was through this dish that the animosity between mother and daughter evaporated, she says. "As the chicken cooked and the rice wine was added, my mother was instantly transported back to Hong Kong and she picked up her chopsticks with relish. This was her comfort food."

The chicken and all the dishes served at 10 Downing Street are "our family recipes which have been handed down from generation to generation", Lisa Tse says.

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

However, cooking for the world leaders 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," she says.

And then the kitchen stove needed to be fixed since it wasn't working. After all that, Lisa Tse says, "I imagined I was back at Sweet Mandarin and cooked my heart out".

Lisa and Helen Tse are the third generation of a family of cooks who have prepared Chinese food and made 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 Tse says.

"My strongest childhood memories are of the kitchen - the click-click of my mother's heels on the tiled floor, the white clouds of steam billowing out as the wok lid lifted, the feel of ivory chopsticks, cold to the touch. School work and a thousand little frustrations and missed Friday night parties evaporated as we sat down to eat."

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

None of their friends in the Manchester Chinese community understood why they were doing it. "They thought we were taking a step backwards," Helen Tse says, adding, "I could see them quietly shaking their heads over the choice we had made. The generation above them understood, though."

Only the bosses of established Chinatown restaurants and supermarkets smiled on the twins with respect.

"It was an acknowledgement that we were carrying the flickering, dimming torch for a new generation, keeping the community alive and making sauces with traditional recipes passed down from generation to generation," Helen Tse says.

Opening the Sweet Mandarin was hard but the slog and late nights were nothing compared to the struggles of Mabel and Lily, she says.

"They arrived in Britain from Hong Kong with nothing, strangers in a foreign country. Everything they had built from sheer perseverance and toil, and everything we had came from them.

"Lisa is our head chef and chief sauce maker," Helen Tse says, adding that her twin is two minutes older than she is. "That two minutes counts and we know who's the boss."

Using the family recipes, Lisa Tse has also substituted thickeners for a gluten-free substitute that does not compromise on taste.

"Our recipes, our sauces are our inheritance, the living part of our family tree, the traditional cooking that my grandmother brought from the homeland and passed down through the generations to me and my sisters.," Helen Tse says. "My mother taught us the basics as our birthright."

Her sister says: "There are many things in this world that divide us, but one thing that unites us is food."

Helen Tse put the story of her family and food into her book Sweet Mandarin, which was published by top British publisher Random House in 2007 and distributed in 33 countries. The book also documents how Chinese people emigrated from China to the United Kingdom.

This year, Queen Elizabeth II awarded the Member of the Order of the British Empire honor to Lisa and Helen Tse for services to food and drink.

Looking to the future, the twins have their dreams.

"We want to make Sweet Mandarin the world's premier brand for all things Chinese. We will be launching a range of woks, kitchen utensils, aprons, also more food and drink products," Helen Tse says.

When it comes to China, Lisa Tse 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, she says.

They hope to have a TV show in China someday so they can show Chinese people where to visit and eat in Britain.

Zhou Heran contributed to this story.

zhangchunyan@chinadaily.com.cn