Into a hot pan add some oil and splutter mustard seeds. Add red chilly and asafoetida and give a good mix. Now into the pan add Bengal gram dal and black gram and gently roast for some time till the contents turn crispy and golden in shade.
Add 2 cups of sooji and sauté till a good aroma comes out. When the Sooji acquires a brown shade off the stove and transfer the contents onto a bowl and allow it to cool for sometime.
Meanwhile into a bowl, add curd, chopped green chilies, ginger paste, curry leaves, salt, and mix well to form a thick paste. Add this paste into the bowl containing roasted semolina. Add enough water and combine thoroughly so that no lumps are formed. Keep this mixture aside for about 15 minutes.
In the meantime, boil some water in the idly cooker and also grease the mould of the your idly trays to avoid sticking of the batter.
Now take the idly batter and add the eno fruit salt and mix nicely. The mixture should foam up. For decoration, you could add some chopped carrots and cashew nuts, after that immediately pour mixture into the Idly Trays and place them in the cooker or steamer. Place a tight lid on the steamer and steam Idlis for exactly 16 minutes on medium heat.
Remove Idlis from the trays by scooping them out with a spoon.
Serve hot with chutney or sambar.