Steam the celeriac for 1 minute, add the beans and steam for another 4 minutes, or until they are tender but still crisp. Then transfer them to a heatproof bowl.
To make the dressing, heat the oils in a wok or a heavy-based frying pan, add the chilli, garlic and ginger and stir-fry over a high heat until they start to brown – do not let them burn. Add the honey, soy sauce and vinegar and boil for 1-2 minutes until thickened.
Stir the dressing into the vegetables and leave to stand for 1-2 hours. Serve at room temperature, garnished with sprigs of coriander.
Variation: broccoli, carrots or parsnips can replace the beans and celeriac.