This light chilled broth, with its gentle Japanese flavours, has a texture somewhere between juice and a light soup. It needs no cooking, but should be chilled well. Use the ingredients straight from the fridge and divide the soup among serving bowls before chilling to make the process even quicker.
Note Coriander cress and shiso cress are available at select greengrocers. Gomasio is Japanese sesame salt and is available from select health-food shops and Asian grocers.