In a pan, add ghee. Add cumins seeds. Let it bloom well.
Then add dried red chillies and curry leaves.
Then add onons, ginger, garlic and tomatoes all at once.
Once the onion comes on top of the oil, add red chilli powder, turmeric, coriander and kasuri methi powder. Cook for a minute or so.
Take out 2 tbsps of tadka and reserve it for using while garnishing in the end.
To the remaining tadka, pour the cooked daal. Mix well. Cook for a minute.
Add coriander leaves and butter. Mix well. Add more water if the gravy is too thick.
Serve.