Wash toor dal and pressure cook it by adding ¼ tsp turmeric powder, salt and enough water for 1-2 whistles.
Soak tamarind in ¼ cup warm water for some time, extract the juice and discard its pulp.
Heat a small pan and add coriander powder, chilly powder, turmeric powder, fenugreek powder.
Roast it till the raw smell goes off.
Add the roasted powder, chopped vegetables, shallots, green chilly, garlic & 1 ½ cup water to cooked toor dal and pressure cook it for 1 whistle.
Add the tamarind juice and mix well. Allow it to boil. Now, reduce the flame and cook till sambar reaches desired consistency.
Heat 1 tbsp oil in a small pan and add mustard seeds. When it crackles, add dry chilly, curry leaf and sauté it and chopped coriander leaves. Pour this to the sambar, add asafoetida powder mix well and remove from flame
Note:- If you are preparing sambar for dosa, it is better without tamarind paste.
Sambar is now ready to be served. It is served well when hot and with dosa or rice