01 - Combine chicken pieces with yogurt, lemon juice, turmeric, and salt in a large bowl. Mix thoroughly to coat all pieces. Let marinate for at least 15 minutes, or up to 2 hours for deeper flavor penetration.
02 - Heat vegetable oil in a large skillet or Dutch oven over medium heat. Add finely chopped onions and sauté for 5–7 minutes until golden brown and softened, stirring occasionally to prevent burning.
03 - Add minced ginger, garlic, and chopped jalapeños to the skillet. Cook for 2–3 minutes, stirring constantly, until fragrant and raw aroma dissipates.
04 - Stir in diced tomatoes and cook for 4–5 minutes until softened and beginning to break down, forming a base for the curry sauce.
05 - Sprinkle coriander, cumin, garam masala, cinnamon, chili powder, and black pepper over the mixture. Stir well to combine and cook for 1 minute to toast the spices and release their essential oils.
06 - Add marinated chicken pieces to the pot, reserving any excess marinade. Cook, stirring frequently, for 5 minutes until chicken is lightly browned on all sides.
07 - Pour in water or chicken broth, scraping up any browned bits from the bottom of the pot. Bring to a gentle simmer, cover, and cook for 15–20 minutes until chicken is cooked through and sauce has thickened to desired consistency.
08 - Taste the curry and adjust salt or heat level as needed. Transfer to serving dishes, garnish generously with chopped fresh cilantro, and serve hot with steamed basmati rice or warm naan bread.