In a cooker, take the Toor Dal. Add equal measure of water to it and cook well.
Once cooked, mash well to obtain a consistent thickness. Keep this aside.
Chop the coriander and tomatoes and slice the green chillies and keep it aside.
In a cooking pan, heat some oil. Then add turmeric powder, mustard seeds, fenugreek seeds, asafoetida and urad dal. Wait until the urad dal starts turning red.
Now add tomato and chillies to this and continue frying.
After sometime, the tomatoes will start to melt...
...then add the mashed dal and mix well.
Now add the chilli powder and salt to taste. Mix well.
Now add coriander for garnishing.
Continue boiling for some time until the rawness of the chilli powder disappears completely. Tomato Pappu is now ready. It goes well with rice.