Wash and soak 1 cup toor dal for 15 to 20 minutes
Cook the dal with 3 cups water and a pinch of turmeric until soft
Mash the cooked dal and set aside
Soak tamarind in warm water and extract the pulp
Heat oil in a pan
Add mustard seeds, cumin seeds, curry leaves, dried red chilies, and a pinch of asafoetida
Add chopped onions and sauté until soft
Add chopped tomatoes and cook until mushy
Add sambar powder, turmeric, and salt
Add chopped vegetables like drumstick, carrot, beans, pumpkin, or brinjal
Pour in water and cook the vegetables until tender
Add the tamarind pulp and simmer for a few minutes
Add the mashed dal and mix well
Adjust water and salt as needed
Simmer until the sambar thickens and the flavors blend
Finish with chopped coriander leaves
Serve hot with rice, idli, dosa, or vada