Heat oil in a heavy-bottomed pan or kadhai over medium heat.
Add mustard seeds, cumin seeds, and asafetida. Add fresh curry leaves. Sauté until aromatic.
Add the chopped onions and sauté until golden brown. This step is crucial for a flavorful base.
Stir in the ginger-garlic paste and cook until the raw aroma disappears.
Add turmeric powder, Kashmiri red chili powder, and coriander powder. Mix well and cook for 2-3 minutes.
Add the tomato puree and cook until the oil separates from the masala.
Add the boiled potatoes and green peas to the masala. Mix to coat them evenly with the spices.
Pour in water to adjust the consistency. Cover and let it simmer for 10-12 minutes, or until the potatoes are tender and the flavors meld together.
Sprinkle garam masala and kasoori methi, and give it a final stir. Let it cook for another minute.
Turn off the heat and garnish with freshly chopped cilantro leaves.