Shiso is the aromatic leaf of Perilla frutescens, an annual herb of the mint family (Lamiaceae) and one of the signature flavours of Japanese cooking. Its scent is unlike any single Western herb — a complex blend of mint, basil, anise and cumin lifted by a clean citrus edge — which is why the green form (ooba or aojiso) is laid beneath sashimi and fried as tempura, while the crimson form (akajiso) colours and flavours umeboshi pickled plums. Korea grows a larger, milder relative, kkaennip, as its own everyday wrapping leaf.