Soak
the sooji in water adding curd and soda bicarbonate. Blend
well with an eggbeater until a creamy batter is formed.
Leave
batter in the mixing bowl overnight. Next day, boil 2 onions
together with the potatoes till done. Peel and mash the
potatoes and slice the onions.
Mix
together adding salt. In a saucepan, heat 2 tbsp oil and
cook mustard seeds till they begin to crackle, and then add
the remaining onion finely sliced, chopped ginger and the
remaining spices. Fry till the onion is golden brown.
Then
add the potato mixture and blend thoroughly. Fry for 5
minutes and keep aside. Place a tava on the fire and spread
with ghee.
Pour 2
large spoonfuls of the batter in the center of the tava and
spread it in circle with a spoon to cover the tava like a
pancake.
Cover
with a large lid for a minute to cook. Remove the lid and
place a spoonful of the potato mixture in the center of the
dosai.
Fold
like an omelets, put a little ghee on the sides of the tava
turn the dosai over and fry till crisp.