1. Peel the potato. Cut it into half. Taking each half piece, slice them to about 2 or 3 centimeters thick.
2. Holding few sliced pieces together cut them into quarters. Repeat this to the rest of the potato.
3. Transfer the small triangular slices into cold water. Set aside.
4. In a pan, heat oil over medium high heat. Add mustard seeds and cumin seeds. Let them splutter.
5. Put asafoetida and add onions. Stir and cook them till soft and translucent for 5 minutes.
6. Put the garlic and stir and cook them for another 3 or 4 minutes.
7. Add red chilli powder, mix well and continue cooking for another 2 or 3 minutes.
8. Put the potato slices, mix well to coat all the pieces in the spice mixture.
9. Season with salt and few splashes of water.
10. Mix, cover and simmer for 20 minutes or till potatoes are soft and tender, stirring every 5 minutes. (Check for water, add more if required in splashes).
11. In a serving plate, serve this curry garnished with chopped coriander leaves.