Start with heating a large pan (or kadhai) on medium-high heat. Add oil to it.
Add cumin seeds and let them sizzle. Then add green chili, onions, ginger and garlic and saute for 3-4 minutes minutes until the onions soften.
Then add tomatoes and spices. Stir them well and let the tomatoes soften for 2-3 minutes.
Add cut pumpkin pieces and water. Mix well. Cover and cook for 10-15 minutes until the pumpkin is cooked through. Check that the pumpkin is softened by mashing a piece.
Add garam masala, dry mango powder, sugar and mix with the pumpkin. You can eat this curry as is with some chunks or mash the cooked pumpkin pieces with a masher in the pot.
Garnish with cilantro and pumpkin curry is ready to be enjoyed with parathas or naan.
Pressure Cooker Method
Follow the same steps as above. After adding the pumpkin, spices and water, pressure cook for 2-3 whistles on medium-high heat. If using an instant pot, pressure cook for 4 minutes on high pressure. Then follow the steps to mash the pumpkin.
If there is any residual water after pressure cooking, which may happen depending on the pumpkin, you can change to saute mode and cook for couple of minutes. Garnish with cilantro leaves and enjoy!
If the pumpkin is not as sweet, then you can add some sugar or jaggery powder, but this is completely optional.
You can choose to eat the pumpkin curry as is with some chunks or you can mash using a masher. Both ways tastes great in my opinion.