1. Prepare the Marinade:

1. In a blender, combine the coriander leaves, mint leaves, green chilies, ginger, garlic, yogurt, lemon juice, and salt. Blend into a smooth paste.
2. Marinate the chicken pieces in this green paste for at least 30 minutes, preferably 1-2 hours for better flavor.

2. Cook the Masala:

1. Heat oil or ghee in a large pan over medium heat.
2. Add the chopped onions and sauté until golden brown.
3. Add the chopped tomatoes and cook until they soften and release oil.
4. Stir in the turmeric powder, cumin powder, coriander powder, and salt. Cook for a couple of minutes until the spices are well incorporated.
5. 3. Cook the Chicken:

1. Add the marinated chicken to the pan along with any leftover marinade. Cook on medium heat until the chicken starts to brown slightly.
2. Cover the pan and let the chicken cook in its own juices for about 10-15 minutes, stirring occasionally.
3. If needed, add a little water to adjust the consistency of the gravy. Cook until the chicken is fully cooked and the oil starts to separate from the masala.
4. Sprinkle garam masala and give it a final stir. Cook for another 2 minutes.

4. Garnish and Serve:

1. Optionally, garnish with a swirl of fresh cream or a dollop of yogurt for added richness.
2. Serve hot with naan, roti, or steamed rice.