For the Idli: Heat 1 tbsp of oil in a kadai and roast the sooji for 2-3minutes till it's fragrant but the colour should not change.
Add the salt and let it cool.
In a bowl, add the roasted sooji, curd, grated carrot and water mix well. Add the soda-bi-card and mix.
Leave it for 10 minutes to rise. In the meanwhile grease the idli mold and heat the water in a steamer.
After 10 minutes, transfer the batter to the mold and steam for 12-15 minutes or till idlis are done.