After soaking grind them in grinder and make a smooth paste. Add 1tbsp salt mix very well. Keep this batter over night for fermentation in little warm place.

For making powder dry roast all these ingredients and salt

Roasting this will be 5 min on medium flame. let it cool make a fine powder in grinder

For making spot idly will take fermatate batter. In a pan add 2 tsb butter, heat on low flame

Now add chopped onion, and chopped tomatoes, coriander leave, cook it for 30 sec

Now add 1/2tbs powder mix it well,

Cook it 30 sec.

Now spread this mixture well very

On top of this mixture well pour 4-5tbs idli batter

Will cover the lid, and let it cook about 10 min in low flame or till idli become completely cook

Now will turn the lidly and cook it for 1 min

Spot idli is ready, it's very crunchy and tasty serve it with coconut chutney