Wash the Urad dal thoroughly for 4-5 times or until the water runs clear. Soak it in enough water for 10-30 mins or more. 

Simultaneously  in a pressure cooker or vessel heat oil and add the cumin seeds. 

Once they splutter add the asafoetida, green chillies, garlic and ginger 

Cook for a min and then add the onions. Saute and cook until translucent. 

Then add the tomatoes along with salt and haldi. Mix well and cook till tomatoes are soft.

Now add the chilli powder and dhania powder.Saute for 1-2 mins. 

Drain the water from the dal and add it to this masala. Mix and cook till any water present in the dal almost dries out.

Then add 1 cup of water. Close the pressure cooker lid and cook for 2-3 whistles. Switch off and wait for the steam to escape completely. 

Open the lid of the pressure cooker.

At this point there still might be some water left in the dal. Add the garam masala, and finely chopped coriander leaves.

Let this dal cook on low heat till the water (if any) completely dries out (approximately 5-10 minutes)

Garnish with some more coriander leaves before serving.

Serve this yummy dal with roti