A Sichuan street vendor's dish, served cold.

1. To poach the chicken, bring a large panful of water to a vigorous boil.
2. Put the chicken into the water, return it quickly to the boil and skim the surface. Add the ginger and spring onions, close the lid and then turn down the heat to a very gentle simmer. Poach at this temperature for about 25-30 mins, depending on the size of the chicken. Test by poking a skewer deep into the thigh joint - if it is not yet cooked, pink juices will ooze out; these will run clear when the chicken is ready.
3. Remove the chicken from the pan and rinse in cold running water. Then either leave in a pan of cold water for an hour or two before use, or just leave to cool and place in the fridge.
4. Make the sauce by dissolving the sugar and salt in the soy sauce and vinegar and gradually stirring in the sesame paste. Add the other sauce ingredients and mix well.
5. Cut as much of the chicken meat as is required into slivers about 1 cm wide, or alternatively hit the flesh a few times with a rolling pin and shred by hand. Arrange on a bed of lettuce and scatter the strips of spring onions over the top.
6. Pour the sauce over the chicken, sprinkle with the sesame seeds and serve.