In a vessel, add 2 tbsp oil, mustard seeds, and cumin seed. Sauté it.
Then add onion pieces and sauté till it is slightly transparent.
Now add tomato pieces and sauté till it becomes soft.
Then lower the flame and add turmeric powder and red chili powder. Mix well.
Now add 1.5-liter water, salt, lauki (dudhi) pieces, pumpkin pieces, drumsticks, and small size onion. Mix and boil for 5-7 minutes.
Meanwhile in another pan, add oil, piece of hing, mustard seeds, cumin seeds, urad dal, chana dal, black pepper, methi dana, coriander seeds, kashmiri dry red chili, coconut pieces, ginger, and garlic cloves. Sauté it
Cool down the mixture and grind it with 1 cup of water. masala paste is ready.
Add masala paste into sambar, also add tamarind water and jaggery. Mix well.
Cover and boil sambar for 25-30 minutes on medium flame.
Then in a bowl, take 2 tbsp besan and ¼ cup water. mix well and add into sambar. boil for 5-7 minutes.
now for sambar tempering, in a tadka pan, add oil, mustard seeds, chana da, methi dana, hing, dry red chili, and curry leaves. Sauté it
Add terming into boiling sambar and mix well.
Garnish sambar with coriander leaves and serve with idli and dosa.