It sounds like something out of the kosher version of Reservoir Dogs. But Jew's ear - recently spotted on sale in a north London organic store – is a regular ingredient in Chinese soup.

Its original name, as the 17th-century writer Thomas Browne pointed out, "concerneth not the nation of Jews". It was called Judas's ear after the disciple said to have hanged himself on an elder tree, a favoured location of the mushroom. If you don't like the name, you can always use the alternative, jelly ear, or the botanical Auricularia auricula-judae.