1. Wash the potato and boil it upto 75% done. Peel the skin make it into cubes and keep aside.
2. Now Slice onion into thinly as possible. Cross cut the green chilli and slice the tomato as well.
3. Heat oil in kadai add mustard and cumin. Once it crackle add onion and saute till it change to transparent. Now add green chilli and ginger garlic paste. Saute until raw smell goes off.

4. Now add tomato and cook till tomato change to mushy.
5. Add all the masala powders one by one. Add salt. Saute nicely until masala oil came out from the edge. Now add the cubed potatoes and mix nicely all the masala have to coat each side of potato. Be careful while doing this there is a change you can mash the potato.
6. If you don't have kashmiri chilli powder you can extra 1/4 tsp of normal chilli. Kashmiri chilli powder gives more colour to your dish not spiciness.

7. Now close the masal with lid and simmer for 2 minutes. Now add coriander leaves and serve hot with roti or rice as your wish..