Pressure cook toor dhal until mushy, keep aside. Add tamarind in warm water and take pulp, set aside. Pressure cook field beans for 3 whistles and keep aside.Heat oil in a pan – add jeera, vadagam and curry leaves let it temper then add onion, garlic and tomato and saute well. Then add broadbeans, potato and sweet potato saute for 2mins. Then add red chilli powder, coriander powder and required salt. Then add water till immersing level.
Once the veggies are cooked then add pumpkin (as it gets cooked faster add it after the other veggies get cooked). Then add little more water if required for pumpkin to get cooked. Once all the veggies turn soft, add mashed toor dhal, jaggery and mix well.
Add 1/4 cup tamarind to 1 cup water and extract tamarind pulp, add it at this stage. Give it a boil then add cooked mochai and allow it to get thicker. Once the veggies are nicely blended with the gravy and is semi thick switch off.