Wash and soak both the rice, urad dal and methi seeds together in water for about 4 hours.
Using the wet grinder, grind the soaked rice and dal into a coarse batter. Add little water when grinding. The batter has to be thicker in consistency. Make sure you grind the batter coarser than you would for normal idli.
Transfer the batter into a large container and add salt. Using your hands mix the batter well. My mother says that using hands to mix the batter helps in fermenting it better and quicker.
Let the batter ferment until it has risen well (about double). It could take 8 to 24 hours depending on how cold it is. Mine took about 24 hours.
Once the batter has fermented, add the sour yogurt to it and mix. This just helps in getting an additional layer of sourness. This could be skipped if you don’t have any.
In a pan, heat the ghee or oil. I used a combination of both. Fry all the ingredients mentioned under the seasoning. Add this to the batter and mix gently to combine.
Grease the idli plates or moulds and pour the batter. I just added a few cashew pieces and then poured the batter. I used small cups/bowls for few and idli mould for few. You could also use a deep plate to make the idli and then slice them into wedges.
Steam the batter for about 15 to 18 minutes. The idli plates would be done in about 15 minutes, but the deeper the dish is, the longer it will take to cook. This idli takes longer than regular idlis to cook.
Serve the Kanchipuram Idli with milagai podi or chutney. The idli is quite spicy and flavorful and just the milagai podi was enough for us.