Make a masala paste of green chillies, coriander leaves, ginger and garlic along with tomatoes. This will have a greenish tinge.
Now heat oil in a kadhai or pan.
Add in cumin seeds and asafoetida and allow to sputter for about 30 seconds. Now add whole spices and cook for a minute more.
Add in the masala paste. Cook for about 10 minutes till tomatoes are well cooked and there is no kachcha or raw smell to ginger-garlic paste. You can see that oil comes out on the sides of the masala.
Take peas in a blender and make a fine paste leaving a few peas coarse or whole.
Once the tomato-green masala is cooked, add the blended peas mixture to it and cook on a low flame for 5 minutes.
Now add water depending upon how thick you want the curry to be.
Add salt and coriander powder. Cover and cook on low heat till the gravy is done. Takes about 5-10 minutes.
Switch off the heat. Add garam masala.
Taste and adjust seasoning.
Garnish with coriander leaves and serve hot.