01 - Combine chicken pieces with yogurt, lemon juice, turmeric, cumin, garam masala, chili powder, and salt in a large bowl. Mix thoroughly to coat evenly. Cover and marinate for at least 10 minutes, up to 1 hour for enhanced flavor penetration.
02 - Heat 1 tbsp butter and vegetable oil in a large skillet over medium-high heat. Add marinated chicken pieces and cook for 5-6 minutes, turning occasionally, until lightly browned on all sides but not fully cooked through. Remove chicken from skillet and set aside, reserving any juices.
03 - In the same skillet, add remaining 1 tbsp butter. Sauté chopped onions for 3-4 minutes until soft and golden brown. Add minced garlic and grated ginger; cook for 1 minute until fragrant, stirring constantly to prevent burning.
04 - Stir in ground coriander, paprika, and cayenne pepper. Cook for 30 seconds to release essential oils. Add crushed tomatoes and sugar; simmer for 5 minutes over medium heat, stirring occasionally to prevent sticking.
05 - Return seared chicken and any accumulated juices to the skillet. Reduce heat to medium-low and simmer for 8-10 minutes, or until chicken is fully cooked through and sauce begins to thicken slightly.
06 - Reduce heat to low. Stir in heavy cream and simmer for 2 additional minutes, allowing flavors to meld. Adjust seasoning with salt as needed. Remove from heat and let rest for 5 minutes before serving.
07 - Transfer to a serving dish and garnish generously with chopped fresh cilantro. Serve immediately alongside steamed basmati rice, jeera rice, or warm naan bread for soaking up the sauce.