Walk past any chaikhana (teahouse) in Samarkand or Bukhara in the evening and you will smell shashlik: chunks of lamb, threaded with little cubes of tail fat, grilled over charcoal and fanned with a piece of cardboard. They arrive on long flat skewers with a heap of raw onion soaked in vinegar, a round of non bread and green tea. The marinade is simple, just onion, cumin, black pepper and salt, so the flavour comes from good lamb and real fire. The usual slip is to pack the meat tightly on the skewer, which steams the middle instead of searing it; leave a little gap between pieces. Chef's tip: grate the onion for the marinade rather than slicing it; the juice tenderises the lamb in a few hours.