Combine the lime juice, tamarind, chilli sauce and brown sugar in a pan, add the rice wine vinegar, mix well, and bring to the boil, simmer for 5 minutes.
Add the ginger, salt and spices, cook for a further 5 minutes.
Mix the cornflour with 2 tsp cold water, then stir into the cooking liquid, simmer for 1 minute, then add the vegetables.