Marinate the Chicken: In a mixing bowl, combine the chicken with yogurt, red chili powder, turmeric, and salt. Let it marinate for at least 30 minutes.
Prepare the Gravy: Heat oil in a large pan over medium heat. Add cumin seeds and let them sizzle. Then, add the chopped onions and sauté until golden brown. Add ginger-garlic paste and cook for another minute.
Add Tomatoes and Spices: Add the pureed tomatoes, garam masala, coriander powder, and salt. Cook until the oil separates from the masala (spice mixture).
Cook the Chicken: Add the marinated chicken to the pan and cook for 5-7 minutes, allowing it to absorb the flavors. Pour in the coconut milk and simmer for 10-15 minutes until the chicken is fully cooked and the gravy thickens.
Garnish and Serve: Garnish with fresh cilantro leaves and serve hot with rice or naan.