Wash Soak Urad Dhal for 6 hours. And wash and soak rice and a pinch of Fenugreek For 10 hours separately
Grind grams to a smooth frothy paste. Grind rice to a pouring consistency and mix both tougher and stir well . Keep aside for 8 to 10 hours.( at 90 degrees F.)

ok, i tried again tonight on a seasoned cast-iron...I still did not get the results I'd like. i had a lot of issues spreading the batter thin (it was sticking to the bottom of my spoon and created holes), then it never got crispy and shiny underneath. I wonder if my bigger problem is the batter--it separates into a watery layer and a heavier grain layer, so maybe I didn't grind the rice fine enough or added too much water? I was using an immersion blender, since I don't have a food processor or regular blender. What do people think?? Pan, batter, combination?

There is a restaurant in Washington DC -- Indique -- that serves mini masala dosas as an appetizer. We had been hoping to go back to a place that was there 25 years ago (Paru's, now in CA), for their dosas that were something like 2 feet across, made by the owner's mother standing behind the counter -- a joy to watch!

thanks everyone! you have confirmed my suspicion that this is the right opportunity to get my cast iron seasoned up--I've been too scared of messing it up but dosas are worth it. i tested a few in my miniature pan last night and they were pretty good!

Same dosa dough/Batter you cam make idli http://en.wikipedia.org/wiki/Idli

I have always used a plain simple non stick pan and it works fine for me. What i do is, i cut the edge of the potato and prick it with a fork , and use the flat side to slightly oil the pan.

Try this egg dosa recipe http://www.food52.com/recipes/1804_egg_dosa_sourdough_crepes_with_egg

Yes Seasoned cast iron or seasoned flat bottom carbon steel wok also a thin or thick flat non stick pan work very well you can see how we make dosa in thin non stick pan (you can find in my picture)

Seasoned cast iron or seasoned flat bottom carbon steel wok or other pan should work--heavy, hot and the seasoning makes them nonstick.