Finely chop the mint leaves and slice tomatoes.
In a pressure cooker, place the onion,red chilli powder, coriander powder, tomato, mint leaves, turmeric and salt for 1 whistle
Run this mix in a blender to make a smooth puree and strain.
In a tempering ladle, heat ghee. Add asafoetida, cumin seeds and mustard seeds. When seeds pop, transfer it over the rasam
Serve hot.
