What you need is
1. Tapioca or Kappa cut into small cubes 2 cups
2. Small onion (shallot) 5 bulbs
3. Green chillies to taste
4. Turmeric powder 1 tsp
5. Salt to taste
6. Curry leaves
7. Oil 1 Tb sp.
8. Mustad and Urad dhal for seasoning.
Cook tapioca with turmeric and salt untill soft. Crush onions and green chillies without adding water. In a pan heat oil and add mustad and urad dhal. Add the cruhed item and fry for 5 minutes. Add curry leaves and cooked tapioca. Add enough water as per your desired consistancy.You can mash it for a thicker gravy. Serve with dosa, idli or chapathy.