Sweet potato puli kulumbu

Ingredients	Quantity
Large sweet potatoes  (plantains, yam or brinjals can be used)	2 (450gms)
Tamarind	Size of orange
Onions	1
Chilli powder	2 tsp
Turmeric	¼ tsp
Salt	to taste
Water	1 lit
Tempering:
Oil	15ml
Mustard seeds	1 tsp
Curry leaves	a few

Soak tamarind in a cup of warm water. Squeeze out the pulp. Peel sweet potatoes, cut into cubes and put into the tamarind pulp. Peel sweet potatoes, cut into cubes and put into the tamarind pulp. Add chopped onions, chilli powder, turmeric, salt and water. Boil down to half its volume. Heat the oil. Add mustard seeds and curry leaves. When they crackle, pour over the curry. Mix well.