Heat oil in a large deep pan on medium heat and add in the cumin, coriander and fennel seeds, along with cardamom pods and peppercorns. As soon as they start to sizzle, add in sliced onion and fry for 2-3 minutes until lightly browned.
Add ginger, garlic and spices, and fry for a few seconds until fragrant. Stir in the tomato paste and combine well with the onion and spices.
Add in the chicken, season with salt and cook covered for 7-8 minutes on low heat. If you prefer a slightly saucy consistency, add in some water and bring it to a slow simmer.
Add in kasoori methi, give it good mix and let it cook covered on low heat until the chicken is cooked through. Remember to keep stirring in between to prevent it from burning.
Garnish with fresh cilantro leaves and serve hot with fresh made rotis or a side of rice.