I started searching through many of the blogs and most of them out of India used a different proportion of rice and urad dhal.
I mix and matched and took this proportion and to my surprise it came out perfectly fine. I almost had tears in my eyes.
Blogs that I referred Priyas and many others.
Idli Rice : 2 portions
Urad Dhal : 1 portion
Aval : 3 table spoons
Salt : 1 table spoon
Baking powder : 2 pinch
Soak Rice and Urad dhal separately for about 6 hours and grind Urad dhal finely for a longer time in the mixer or grinder. Remove this into bowl. Now grind the rice coarsely (not too fine). Mix this with Urad dhal batter along with salt. Mix it in your hand so that the heat helps fermentation. Close it and keep it in a owen overnight for fermentation. Add baking powder mix well and make idlis the next day. It has to come out soft and fine hopefully ;) Serve with chuttney or any kind of sambar. We had it with tomato sambar the other day.
I feel for getting soft idlies we gotta be lucky. Once it might be fine, but with the same proportion things might not work on another other day.