Blend rava, rice flour and buttermilk to make a thin batter, add asafoetida and required salt. Stand the batter for at least 6 hours.
Wash and finely chop the ginger, green chillies and curry leaves. Chop the coconut and cashew nut into very small bits.
Crush the peppercorns and cumin seeds. Heat the ghee and roast peppercorn and cumin seeds in it and add to the batter.
Mix the chopped greens, coconut and cashew into the batter. Stir well.
Grease a non-stick tawa, smear little oil. Pour a ladle full of the batter and spread by swirling the tava.
Pour a tablespoon oil around and on the dosa.
Cook till it is crisp and golden in color. Remove and serve hot.