Wash and dry the chicken pieces. Marinate for 30 minutes with 1 tablespoon ginger & garlic paste, salt, and 1 teaspoon black pepper powder.
Heat 5 tablespoons of vegetable oil in a saucepan. Add marinated chicken pieces and fry for 1 minute on high heat. Reduce the flame and cook for just 10 minutes. (Half cook the chicken)
Heat another saucepan with 5 tablespoons vegetable oil or ghee. Fry roughly chopped onion till light golden. Then add roughly chopped tomatoes and chopped green chilies. Fry for 2 minutes and remove from heat. Cool and grind to a smooth paste.
Add the onion-tomato paste to the half-cooked chicken and cook. Stir well and add 1 teaspoon red chili powder, 1 teaspoon red chili flakes, and 1 teaspoon cumin seeds. Cook for 2 minutes and then add 1/2 teaspoon garam masala powder and 2 tablespoons kasoori methi. Finally, add 1/4 cup cream and chopped coriander leaves, stir well, cover, and cook the curry till the chicken is fully done. This will take another 5 to 10 minutes.
Garnish the curry with ginger, green chilies, and coriander leaves, and also add some more ghee or butter to give a nice shine on top.
Serve hot with naan or roti.