firstly, peel the skin of the sweet potato. you can use white or brown sweet potato.
grate the sweet potato uniformly. keep aside
n a pan heat 3 tsp oil and saute 1 tbsp urad dal, 1 tbsp chana dal, 3 dried red chilli and few curry leaves
add in grated sweet potato and saute for 5 minutes.
saute until the sweet potato is cooked well.
cool completely and transfer to the blender.
add in ½ cup coconut, small ball sized tamarind, ½ tsp salt and ½ cup water.
blend to smooth paste adding water as required.
now prepare the tempering by heating 3 tsp oil and splutter ½ tsp mustard, ½ tsp urad dal and few curry leaves
pour the tempering over the chutney and mix well
finally, enjoy sweet potato chutney with hot steamed rice or dosa.