Wash rice and dhal and soak each separately overnight or for at least seven to eight hours. Drain, remove skin from the dhal.
Grind rice and dhal together with the cooked rice and water in a blender until smooth. Strain batter through a fine sieve. Add salt and mix well. Leave to ferment for eight to 10 hours. (Refrigerate if not using it for breakfast.)
Grease an iron griddle lightly with gingili oil. Pour a ladleful of batter onto the centre of the griddle. Spread the batter immediately with the back of the ladle starting from the centre in a clockwise motion to make a thin pancake.
Cook for about half a minute or until the underside turns slightly brown. Remove thosai from the griddle and repeat till the rest of the batter is used up. Serve thosai with dhalca chicken curry.