Soak 1 cup chickpeas overnight. Drain and rinse well the next morning. Add 1 cup water, ½ teaspoon salt, and ¼ teaspoon turmeric. Pressure cook until the first whistle, then reduce the heat and cook for another 8–10 minutes. Switch off and allow the pressure to release naturally. Open and keep the cooked chickpeas aside, reserving the cooking liquid.
Grind onion and ginger together to a fine paste. Blanch the tomatoes, peel, and grind to a smooth paste. Grind cashews and yogurt together to a fine paste. Keep all the prepared ingredients ready before starting to cook.
Heat a heavy skillet and add sesame oil. Add the ground onion-ginger paste and sauté, stirring continuously, until the onions turn deep golden brown. Add another tablespoon or more of oil if required.
Add the tomato paste and cook for 2 minutes. Add the ground cashew-yogurt paste and cook for another 5 minutes, stirring well.
Add ½ cup hot water and deglaze the pan, scraping the bottom to release any browned bits. Cook until the gravy thickens. Add chilli powder, cumin powder, and half of the special garam masala. Cook for 2 minutes. Drizzle in 1 tablespoon sesame oil and cook well.
Add the cooked chickpeas along with some of the reserved cooking liquid. Cook over medium-high heat for 3 to 5 minutes, stirring or tossing occasionally.Add half of coriander leaves.
Add1 cup chicken stock, vegetable stock, or hot water and simmer for 8–10 minutes, allowing the chickpeas to absorb the flavours. Add more hot water or stock at any stage, according to the consistency you prefer.
Sprinkle in the chaat masala and the remaining garam masala. Adjust the salt. If required, add a little more hot water, then add the remaining coriander leaves and bring the curry to a boil.
Garnish with finely chopped coriander leaves, chopped green chillies, and julienned ginger.
Cooking chickpeas - Pressure cook chickpeas with water for one whistle. Lower the flame and cook for 8-10 min. Switch off and open once it cools down.
If you prefer less heat, deseed the green chillies before chopping.
How to blanch tomatoes - Bring a pot of water to a boil. Make a shallow cross-shaped cut at the base of each tomato and carefully place them in the boiling water. Blanch for 1–2 minutes, or until the skins begin to loosen. Transfer the tomatoes immediately to cold water. Once cool enough to handle, peel off the skins and grind the tomatoes to a smooth paste.
When I'm in a hurry, I skip the cold water bath. I simply boil the tomatoes until the skin peels, drain them, peel off the skin, roughly chop, and grind them to a smooth paste.
Chaat masala, tomato paste - I have used store bought chaat masala and tomato paste in this recipe.
Homemade chicken stock imparts umami flavour.