You need rice flour, gram flour, Bombay rava, two potatoes, a small cup of curd, and water. You take a mixer jar first. You add one cup of rice flour, one cup of gram flour, and half a cup of Bombay rava into it. You peel two potatoes, cut them into small pieces, and drop them in. You add a quarter cup of curd and a little water, and grind everything into a smooth paste. You cover this batter and keep it aside for some time. You mix the batter well after 10 minutes and add salt. You squeeze half a lemon over the salt. You mix the batter thoroughly now. You add a little water if you need to adjust the consistency. Your instant dosa batter is ready.