Soak urud dal and rice separately for 2 hours. Grind them separately.  Grind the cooked rice to a paste.  Mix all together. Keep it to ferment for 6 to 7 hours or overnight. Add salt, mix well.

Now in a 'dosa pan' rub oil and pour ½  cup of  fermented batter  and spread it with a spoon into a very thin dosa.  Turn over and cook the other side. Serve with pickle or chutney.

Serves 4