Mix together coriander powder, chilly powder, turmeric powder and methi powder in water and keep it aside.

Heat oil in a kadai or a pan.

Add mustard seeds and when they crackle, add dried red chillies.

Add small onions and saute for a while.

When it turns slight brown color, pour the water mixed with all the powders into it.

Add potato and tomato.

Add tamarind water and allow it to boil.

Keep the heat on medium.

When it starts making bubbles, add curry leaves and let it boil for few more seconds.

:- Serve with rice.

:- You can add more vegetables, if you wish. :- You can prepare the curry without vegetables too.