In a mixing pot / bowl, add 1 cup rava / sooji and 1 cup buttermilk.
Add rice flour, wheat flour and 3 cups of water. Mix well until there are no lumps. Set aside.
Now, chop a big onion, green chilli, ginger, curry leaves, coriander leaves finely. Crush a tsp of whole pepper. Add all these ingredients to the batter.
Add a tsp of cumin and salt as required
Rava has to be soaked up for 20min. So set aside the mixture.
Check batter consistency after 20 minutes as Rava bulges, add water if required. The batter consistency should be watery, than the regular Rice Dosa batter.
Grease the Dosa pan with few drops of oil (if you use non-stick pan, no need of greasing) and pour Dosa in the required shape.
Sprinkle a tsp of oil along the sides of Dosa.
Cook covered with a lid for 2 minutes for a crispy Dosa.
Take out and serve hot along with your favorite chutney.