01 - In a large bowl, combine all marinade ingredients and mix well. Add chicken pieces, coating thoroughly. Cover and marinate in the refrigerator for at least 1 hour, ideally overnight for maximum flavor penetration.
02 - Preheat oven grill or grill pan to high heat. Arrange marinated chicken pieces on a foil-lined tray or skewers. Grill for 8–10 minutes, turning once, until lightly charred and just cooked through. Set aside.
03 - Heat butter and oil in a large skillet over medium heat. Add onions and sauté for 5–6 minutes until golden brown. Stir in minced garlic and ginger paste; cook for 1 minute until fragrant.
04 - Add crushed tomatoes, ground cumin, coriander, paprika, garam masala, sugar, and chili powder. Simmer, stirring constantly, for 10–12 minutes until thickened and oil begins to separate from the mixture.
05 - Transfer sauce to a blender and blend until completely smooth, or use an immersion blender directly in the pan. Return the smooth sauce to the skillet.
06 - Add grilled chicken pieces to the sauce. Stir in heavy cream and kasuri methi. Simmer gently for 8–10 minutes until flavors meld together and chicken is tender. Adjust salt to taste.
07 - Garnish generously with chopped fresh cilantro. Serve hot accompanied by steamed basmati rice or warm naan bread.