1. Pressure cook chana with some salt & water for about 3 whistles or until done; Keep aside.
2. Dry roast red chilies for a minute or two; Grind to a paste with coconut and tamarind; Add water as required.
3. Combine the cooked chana, potatoes and yam in a vessel; Add the masala paste and boil for a couple of minutes;
4. Add salt as required and mix well; You could even add some water to get the desired consistency.
5. Temper with mustard seeds and curry leaves; Serve hot with steamed rice, idlis or even dosas!

Note:

1. You could use any oil for tempering, but sticking to the authentic way of using coconut oil takes this dish to an entirely different level.
2. The flavor the coconut oil adds to the dish is unmatched!!!

Courtesy: http://maneadige.blogspot.com/