Heat oil in a wok with salt. Add potato chunks and fry for 2-3 minutes on medium heat. Then fry for another 2-3 minutes on high heat until golden from all sides. (Also prick with a fork to check tenderness.) Work in two batches.
Dry roast cumin, coriander, red chilli flakes and salt in a pot for few seconds.
Add fried potatoes and fresh green coriander. Coat throughly with seasoning.