Create the Vibrant Green Paste: In a blender, combine the lime juice, chopped tomato, fresh cilantro, green chilies, ginger, and ¼ teaspoon of salt.
Add 4–6 tablespoons (90 ml / 3 fl oz) of water, or as needed to get the blades moving, and blend into a smooth, bright green paste.
Prepare the Chickpeas: Drain the chickpeas, reserving the liquid (this is aquafaba and is great for the curry base).
Set both the chickpeas and the liquid aside.
Build the Curry Base: Pour the oil into a medium nonstick frying pan over medium heat.
Once hot, add the asafetida. A few seconds later, add the cumin seeds and let them sizzle until fragrant, about 15-20 seconds.
Add the chopped onion and stir-fry for 7–8 minutes, until the edges begin to brown.
Stir in the ground coriander and cook for another 30 seconds.
Combine and Simmer: Add the drained chickpeas, ½ teaspoon of salt, and 1½ cups of the reserved chickpea liquid, water, or a combination of both.
Bring to a simmer, then cover, reduce the heat to low, and cook gently for 20 minutes.
Finish the Curry: Stir the green paste from the blender into the pan.
Bring everything back to a simmer, cover, and continue to cook gently for another 20 minutes to allow the flavors to meld.
Taste and adjust the salt if needed. If using, stir in the chaat masala just before serving.
Let the finished curry rest for 10-15 minutes off the heat before serving. This allows the flavors to meld and deepen for an even more delicious result.
