01 - Combine yogurt, lemon juice, cumin, coriander, garam masala, chili powder, and salt in a large bowl. Add chicken pieces, toss to coat thoroughly, and marinate for at least 15 minutes, up to 2 hours for deeper flavor penetration.
02 - Heat 1 tablespoon butter and oil in a large skillet over medium-high heat. Add marinated chicken and cook until browned and nearly cooked through, approximately 5–7 minutes. Remove chicken from pan and set aside, reserving any juices.
03 - In the same pan, add chopped onion and sauté for 3–4 minutes until soft and translucent. Add minced garlic and grated ginger, cooking for 1 minute until fragrant.
04 - Stir in crushed tomatoes, cumin, paprika, garam masala, chili powder, sugar, and salt. Simmer for 10 minutes, stirring occasionally, until the sauce thickens noticeably and deepens in color.
05 - Reduce heat to low. Stir in heavy cream and 2 tablespoons butter, continuing to stir until completely melted and the sauce achieves a smooth, velvety consistency.
06 - Return chicken with any accumulated juices to the pan. Simmer gently for 5–7 minutes until chicken is fully cooked through and flavors have melded together.
07 - Garnish generously with fresh chopped cilantro and serve immediately with basmati rice or warm naan bread.