1. First soak rice, chana dal at least 2 to 3hrs..
2. Cut the Ridge guard with the skin( even we can use only the tender skin), onion.
3.Now blend all the ingredients with very less amount of water, the batter should be like Moong dal dosa consistency.
4.Heat the pan, spread the batter into thin dosa. Add butter or oil, cook well and serve with chettny..