We call this Karunai Kizhangu (tuber) or Pidi Karunai. Karunai Kizhangu Masiyal (or literally, Yam Mash) is the most common and one of our favourite recipes that we prepare with this tuber. It takes very basic spices.
KARUNAI KIZHANGU MASIYAL (YAM MASH)
Ingredients :
Mini Yam/Karunai Kizhangu - 4 to 5
Green chili - 1, slit
Ginger - 1 inch piece, chopped
Tamarind - half lemon size, juice extracted
Lemon - 1 medium
Salt to taste

For tempering:
Sesame Oil - 1 tsp
Mustard seeds - 1/2 tsp
Split Urad dal - 1/2 tsp
Hing pwd - 1/ 4 tsp Curry leaves, a few

Method:
1. Peel, wash and leave the yam (halved) in some rice water to remove the itchiness.
2. Wash again, cut into thick slices and pressure cook upto 3 whistles. Remove and mash while still hot.
3. Transfer to a thick bottom saucepan along with the tamarind juice.
4. Add the slit green chili, ginger and salt and let simmer on low for 4-5 minutes. Keep stirring occasionally.
5. Remove from flame. Prepare tempering by heating oil, adding the rai, urad dal, hing and curry leaves. Pour over the Masiyal/mash and serve hot with rice.

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