Cut the lamb into thin slices across the grain. Combine the sherry, soy sauces and sesame oil, add the lamb and toss until well coated. Leave to marinate for 15 minutes, then drain, reserving the marinade.

Heat the oil in a non-stick frying pan, add the meat and about 2 teaspoons of the marinade and fry briskly for about 2 minutes, until well browned. Add the garlic, ginger, leek and spring onions and fry for a further 3 minutes.

Transfer to a warmed serving plate, garnish with the spring onion flowers and serve immediately.

This recipe originated in the northern part of China. The lamb is always cooked in a wok there but a frying pan is a satisfactory substitute.