Soak the rice, black gram and fenugreek seeds in water for a few hours and grind to a fine smooth dosa batter. Keep aside to ferment for few hours. This can be done a day before too.
Mix salt, 1/2 tsp ginger-garlic paste and marinate the chicken pieces in this mixture for few minutes.
Make a fine paste of chopped onions and cumin seeds. To this, add the remaining ginger-garlic paste, salt, chilly powder, garam masala and mix well.
Apply this mixture to the chicken pieces and keep aside for 30 minutes.
Heat oil in a deep frying pan.
Take each chicken piece, dip in the above dosa batter and fry in the oil until golden brown.
:- Serve hot.