Add oil to a pan and heat it. Add cumin allow them to splutter.
Add ginger and fry for 1 minute on a medium heat until it turns aromatic.
Next add fine chopped onions (or tomatoes) and sprinkle salt.
Saute until the onions turn golden. This takes some time but it is important to cook them until caramelized. (You may skip the onions and just add tomatoes. If so, then saute tomatoes for 2 mins and then cook them covered until soft and mushy).
Add pumpkin and fry for 2 to 3 minutes. Sprinkle red chili powder, turmeric and garam masala
Mix everything well and saute for about 2 to 3 minutes until the red chili losses its raw flavor.
Cover and cook on a low flame, stirring occasionally to prevent burning.
After a while, pumpkin begins to release moisture, if it doesn't sprinkle little water as needed.
When soft cooked, switch off the stove and garnish kaddu ki sabzi with chopped coriander leaves.