Make batter with soaked dal.and rice with little batter as idli batter and keep for rest for 1 hour.

Now make stuffing, heat oil in a pan add, mustard seeds, splutter, add Finely chopped onion,saute and add tomato cooked well.

Add boiled mashed potatoes and all masale to taste.

Now take a non stick dosa tava, add oil, clean with tissue paper, spread dosa batter and keep potato stuffing.

Aplly oil on all sides of dosa.

When it will crispy fold and serve hot.

Serve with coconut chutney and sambhar.