Peel and wash the sweet potatoes. Cut into thin long pieces. Heat a thick bottomed pan and add 3 tbsp oil. Add sliced onions and fry till light brown. Remove from oil, let cool and make a paste. Heat the oil again and add the onion paste. Fry for few seconds and add ginger garlic paste and turmeric. Let it leave raw smell and add the sweet potatoes and green chillies. Add little salt. The mixture is dry at this point so be carefull not to let it burn. cover and cook for about 15 min, stirring occasionally. When the potatoes are soft add red chilli powder and salt to taste. Add the peanuts and coconut paste. fry for 2 min and add tamarind paste and 2 cups water. Cover and cook for another 5-10 min. when the gravy thickens and oozes out oil, add 1/2 tsp sugar and coriander powder. simmer for 1 min , season with coriander leaves and turn off heat.

You can replace sweet potatoes with raw bananas and have tasty aratikaya pulusu. You have to taste it to know how great it is! Soak the banana pieces in cold water with pinch of turmeric and salt.