1. Soak the tamarind in hot water for about 20 minutes.
2. Work the pulp loose with fingers and strain through a sieve.
3. Press down with the back of a spoon to squeeze all pulp. Set aside.
4. Boil the potatoes in salted water till tender and peel when cool
5. Roast the Kashmiri chillies in an oven or a skillet.
6. Remove the stalk and seeds, crush the chillies coarsely and mix with the garlic paste and ground cumin seeds.
7. In a pan heat the oil until smoking hot, put in the curry patta then add the garlic, chilli and cumin paste.
8. Immediately turn off the stove.
9. Stir to mix then add the boiled potatoes and mix.
10. Cover and let it stand for 1 hour.
11. Add the tamarind pulp and mix.
12. Serve warm.