Drain the water out. Grind rice flour, raw rice and split bengal gram to make a smooth paste using enough water to get a batter of coating consistency.
Heat a non-stick tava
When hot, pour a ladle full of the batter and spread it using circular motion to make a paper thin dosa.
Cook on one side, pouring a little oil along the edges while cooking.
When it becomes crispy, roll it up.
Repeat the same procedure for the remaining batter.