Heat the oil in a deep saucepan or a medium-sized wok. Fry the onions and garlic until the onions are caramelised.
Add the salt, cumin, coriander, turmeric and red chilli powder. Cook for a minute and then add the tomato. Cook the sauce until it begins to thicken.
Add 4 tablespoons of water and stir. Stir in the chickpeas. Mash in a few of the chickpeas, cover and simmer for 5 minutes. Add the ginger and garam masala. Cook for another minute.