Put all the chopped vegetables in to a cooking pan along with tamarind juice. Cook it in medium flame along with jaggery and turmeric powder. Let the vegetables turn soft but not mushy.
While the vegetables are still cooking, get the coconut masala ready. Dry roast the split black gram lentils in a seasoning pan till they turn brown. Transfer this to a mixer jar and also add grated coconut, green chillies, coriander seeds and little water. Grind everything together to fine puree.
Ensuring all the vegetables for done-ness add coconut masala from above step to the pan. Finally add salt and water to adjust consistency. Combine and bring the curry to a good boil. Switch off the flame.
Heat a seasoning pan with cooking oil, mustard seeds and curry leaves. As the mustard seeds crackle add the seasoning to curry.
Mixed vegetable curry is ready to serve with rice. It can also be relished with chapati and dosa.