First, make the pickle. Combine the lemon juice, onion and pinch of salt in a small bowl. Set aside.
Heat half the ghee in a frying pan and fry the paneer for 10 mins, stirring until lightly brown and crisp on all sides. Scoop out onto a plate using a slotted spoon.
Heat the rest of the ghee in the pan over a high heat, and fry the onions for 5 mins until starting to brown at the edges. Add the garlic, turmeric, chilli powder, cardamom seeds, chilli, curry leaves and pepper, and stir-fry for 5 mins until the onions are caramelised.
Return the paneer to the pan along with the chickpeas and a large splash of water, and simmer everything for 5 mins until the liquid has evaporated and the mixture is sticky. Season with salt, then spoon into a dish and top with the coriander and pickled onions.