The roast beef trolley waiter is one of the hardest-working members of staff at the Mandarin Grill. All through lunch and dinner, the gleaming silver cart is wheeled across the room. Hungry diners' faces light up when they see its smooth arrival, the domed lid lifted back with a flourish before the waiter carves their cut of choice (rare, medium or well done; thick or thin) in front of them. It's good to see the roast beef trolley alive and well in Hong Kong. As well as the Mandarin Grill, they can be seen at Amigo's in Happy Valley, Lawry's in Causeway Bay and Hugo's at the Hyatt Regency in Tsim Sha Tsui, as well as a smattering of private members' clubs. For a while the roast trolley fell out of favour in its spiritual home, London, where it was particularly popular at Simpson's in the Strand in the second half of the 19th century. But there, too, the trolley has become fashionable again in a return to high-class, elegant values, and younger chefs have put this traditional mainstay back on the restaurant floor. The trolley at the Mandarin has been in situ since 1975. Giovanni Valenti, who joined the Mandarin Grill as manager in 1979 - and is now concierge ambassador for the Mandarin Oriental hotel - remembers it being in constant service ever since. 'It adds a certain theatre to the dining experience,' he says. This one is a particularly beautiful design: entirely silver plated with art nouveau detailing and clawed feet. It's the same design as the one at the Raffles Grill in Singapore, which the staff buried in the Palm Court garden when the Japanese occupied the hotel during the second world war and dug up afterwards. But the trolley is not just for show. As well as the practicalities of housing the carving tray, plate holder and various gravy and sauce boats in one ostentatious package, traditionalists claim it enhances the meat. 'The trolley is heated in such a way that it is able to hold an entire joint of beef without ever cooking it further, but allowing it to rest,' says Valenti. Below the carving tray is a pan of water heated by burners that keeps the meat warm and moist. Over at the Convention and Exhibition Centre, the roast beef trolley is a staple at the Congress restaurant and is available for the many private functions held at the venue. 'It is part of an elegant dining experience and allows showmanship from the waiters,' says Maurice Kong, the venue's food and beverage director. Kong also believes the trolley has a practical, not just an aesthetic, function: 'The trolley helps keep the meat warm and thus ensures the quality when it is being served, yet it does not change the taste of the meat.' Trolley designs differ greatly. At the Foreign Correspondents' Club in Central, the roast trolley - which has been rolled out since 1976 and is used to serve roast strip loin beef every Thursday - has a bulbous brass dome and sturdy wooden legs. At Lawry's, the trolley has taken on an American influence, with the 'signature silver cart' looking like a giant armadillo. Lawry's cart was designed by the restaurant's founder in 1938 to bring 'the English method' to cooking prime rib of beef. Each one was said to have then cost the same as a new Cadillac. The original is still in use at Lawry's in Beverly Hills.