In a pan add coriander seeds, red chillies, methi, jeera, pepper and curry leaves. Roast in low flame until a nice aroma comes. Turn off and allow to cool.
Crush garlic and keep aside. Meanwhile cook toor dal.
In a pan, add chopped tomato, curry leaves, turmeric powder, crushed garlic and water. Boil for 2 mins.
Now add tamarind water and bring to boil for 2 mins.
Add jaggery while boiling.
Meantime grind roasted items. Grind to a coarse texture.
Now add salt and ground rasam powder.
Boil till its frothy.
Stir in cooked toor dal, mix well and turn off the rasam.
For tempering add ghee and when it's hot, add mustard and asafoetida and pour in rasam.
Now its ready to serve with hot rice.