Soak tamarind in about ¼ cup of hot water, mix it well and squeeze out the pulp, recipe needs about 2 tablespoons of pulp. Set aside.
For gravy dry roast chilies, mustard seeds and coriander over medium heat for about 1 minute.
First grind the dry ingredient red chili, mustard seeds, and coriander, into coarse powder. Add coconut, tamarind pulp and ¼ cup water to make it into a paste. While blending use water as needed to make paste. If you prefer mild take the seeds out of red chili before blending. Set aside.
Heat the oil in a sauce pan add mustard seeds red chilies, and curry leaves, as seeds crack add potatoes, salt and turmeric. Stir for about 1-2 minutes.
Add coconut paste and mix it well; add about 1-1/2 cups of water.
After potatoes come to boil let it cook covered for 4-5 minutes over medium heat.
Note: The dish absorbs water while sitting. Add more water as needed to keep the gravy consistency of your liking. Let it cook on low heat for few more minutes.
Potato with Coconut Gravy is ready to serve.