Dry roast the semolina till it is aromatic. Remove from fire and allow it to cool.
Mix in semolina, curd, water, and salt to form a smooth paste. Let it stand for a minimum of 10 minutes so that the semolina can soak in the liquids.
When ready to cook, add in 1 tsp of Eno fruit salt. Mix well stirring in one direction only.
Fill in the water into steamer to the desired level making sure it does not touch the idli mould.
Grease the idli mould. Pour in the idli batter uptil three-fourths. This ensures that the idlis have space to rise.
Cook for 10 minutes or until the idlis are cooked. Let it stand for 5 minutes.
Demould the idlis and keep aside.
Heat oil in a pan.
Add in the mustard seeds and cook until they crackle. Add in the curry leaves.
Mix in the idlis. You can also add a bit of salt or red chillies here.