Cut the Potatoes in long pieces & cut the onions.
Heat oil in kadai. Add kalonji & dry red chilli. After splattering, add Potatoes & green chillies. Add turmeric powder. Fry for 2 minutes.

Then add onions. Fry it for 5 minutes in medium to high flame. Add salt. Fry it for 2 minutes in high flame. It's done. Now serve it with Roti or steamed Rice & Dal.