The coconut paste: Grate coconut. Put into blender with the cashewnuts and 60 ml coconut water. Blend into a fine paste.
Heat 75 ml of the reserved oil in a pan, add cumin and mustard seeds, urad dal, whole red chillies and curry leaves, saute over medium heat until the seeds begin to crackle. Add the onions and saute until golden brown. Then add tomatoes and red chilli powder, turmeric, coriander and salt, cook until oil leaves the masala. Reduce to low heat, add the coconut paste and simmer for 2 minutes. Remove the pan, add yoghurt, stir, add water (approx 400 ml), return to heat and bring to a boil. Now add the deep fried okra and simmer until napped in the gravy. Adjust seasoning.