Drain and pressure cook the chana with 3½ cups water, salt and the tea leaves tied in a piece of muslin cloth for 6-8 whistles. Drain and reserve the cooking liquour.
Heat olive oil in a non stick pan. Chop onion. Add cumin seeds to the pan and when they change colour, add onion and sauté.
Add ginger paste, garlic paste and a little water and sauté for 1-2 minutes. Add coriander powder, cumin powder, chana masala, red chilli powder and mix. Add chana and some cooking liquour, salt and mix. Cover and cook for 10 minutes on medium heat.
Add darkly roasted cumin powder and mix. Transfer into a serving bowl, garnish with coriander leaves and serve hot with bhature.