Heat oil in a karahi or heavy-bottomed wok over high heat until shimmering. Add chicken pieces in a single layer with 2 cm space between them and sear 3-4 minutes per side until golden-brown crust forms. Remove chicken and set aside.
2 lbs bone-in chicken pieces, 0.33 cup vegetable or mustard oil
Lower heat to medium, add cumin seeds to the same oil, and cook 30 seconds until aromatic and slightly darkened. Stir in ginger-garlic paste and cook 1 minute until raw smell disappears, stirring constantly to prevent sticking.
2 tbsp ginger-garlic paste, 1 tsp cumin seeds, 0.33 cup vegetable or mustard oil
Add diced tomatoes, red chili powder, salt, and green chilies. Stir well, increase heat to medium-high, and cook uncovered 15-20 minutes, stirring every 2-3 minutes, until tomatoes break down completely and oil separates from the sauce and pools at the edges.
4 large tomatoes, 3-4 green chilies, 1 tsp red chili powder, salt
Return seared chicken to the pan, coat pieces with sauce, reduce heat to medium-low, and cover. Simmer 12-15 minutes until chicken reaches 165°F internal temperature and no pink remains at the bone.
2 lbs bone-in chicken pieces
Sprinkle garam masala over the chicken, stir gently to coat, and turn off heat. Add chopped fresh coriander and remaining green chilies, cover, and let rest 5 minutes before serving to allow flavors to meld.
0.5 cup fresh coriander leaves, 1 tsp garam masala, 3-4 green chilies
