Heat oil in a heavy-bottomed pan over medium heat. Add the cumin seeds and let them sizzle for a few seconds. Add the chopped onions and cook, stirring frequently, until they turn deep golden brown.

Stir in the ginger-garlic paste and cook for 1 minute until the raw smell disappears. Reduce the heat to low and add the ground coriander, Kashmiri chilli powder, and turmeric. Stir continuously for 30 seconds.

Pour in the tomato puree and salt. Cook over medium heat, stirring occasionally, until the oil begins to separate from the tomato mixture.

Add the rinsed chickpeas and water to the pan. Use the back of a spoon to mash a small handful of chickpeas against the side of the pan to help thicken the gravy. Bring to a boil, then reduce the heat to low, cover, and simmer for 15 minutes.

Remove the lid and stir in the amchur and garam masala. Simmer uncovered for another 5 minutes until the gravy reaches your preferred thickness. Serve hot.