Wash and soak rice in enough water for about 2 hours. Drain the water and keep it ready.

Peel the skin off from raw banana and chop it in to big chunks. Take drained rice, chopped raw banana and coconut in a mixer jar and grind them gether in to fine batter. Add water to obtain the batter of regular dosa batter consistency.

Heat a dosa griddle and pour a ladle full of batter on it. Using the back of ladle spread like dosa and cook it covering with lid. It's not necessary to flipping it over to cook the other side.

When the dosa gets cooked, using flat ladle loosen the edges and remove it from griddle. Continue with rest of the batter.

The raw banana dosa batter doesn't require fermentation. You can instantly make the dosa.

While grinding the dosa batter, add water in steps and adjust consistency to regular dosa batter.

If you ferment the batter, the dosa would stick to the griddle and removing would be difficult.

I have used Iron griddle to spread the dosa, you can use non-stick too.