"Ubiquitous throughout Yunnan, this classic chicken soup is superb because of its ingenious cooking method. The secret lies in the qi guo, the unique Yunnan ceramic pot with a tapered cone or chimney in the centre. A heavy lid fits snugly over the pot and it is set over a saucepan over boiling water. Steam rises through the chimney and condenses under the lid before falling into the pot, creating a heavenly, nourishing consommé. You can make the soup without this steam pot by simply steaming the soup in a covered bowl over a saucepan. The poor man's ginseng and astragalus huang qi are said to combat ageing, but you can always make a simpler version with ginger, soy, rice wine and dried shiitake and it'll be delicious."
Note Dried longan, dried Chinese dates (jujubes), poor man's ginseng (Codonopsis pilosula) and astragalus huang qi (Astralagus propinquus) are available from Chinese grocers, sometimes in the form of a packet of tonic soup mix. The cooking time may vary depending on the flow of steam and the age of your chicken.