Wash all the 5 cups of spinach leaves properly and blanch it . Remember for retaining the bright green colour ,its important that after blanching you put all the spinach in cold water filled with ice cubes.Do not boil spinach ,one minute of blanching is more than enough.
Make a smooth puree of blanched spinach and keep it aside.
Take a wok /Pan.
Add oil to it .
When its hot ,add cumin seeds and asafoetida.
Let them crackle.
Add Thinly chopped onion to it and saute it on the medium flame.
When it looks transparent add ginger garlic paste to it .Saute till the raw smell is gone .It will take around one minute.
Add coriander powder,chopped tomatoes ,kashmiri red chilli powder and little bit of salt to it .
Saute it on low/medium flame till all the tomatoes are soft and mixed with spices.
Add chopped spinach at this time and saute for 1 minute.
Add spinach puree to it .Mix it nicely into the onion tomato mix.Switch off the flame and keep it aside.