Blend cashews, almonds, desiccated coconut, and water into a smooth paste.
In a large bowl, combine the nut paste with all the marinade ingredients including thick curd, ginger-garlic paste, slit green chilies, browned onions, mint leaves, coriander leaves, green chili sauce, red chili sauce, dark soy sauce, turmeric powder, Kashmiri chili powder, coriander powder, garam masala, salt, pepper, lemon juice, and ghee.
Add the bone-in chicken to the marinade and coat well. Marinate for at least 2 hours, or overnight for best flavor.
Heat neutral oil in a heavy pan over medium heat. Add curry leaves and let them crackle.
Transfer the entire marinated chicken into the pan. Cook on low to medium heat, covered, for 40–45 minutes, stirring occasionally to prevent the masala from burning.
Once the oil separates, the gravy deepens to a darker red, and the chicken becomes tender and almost fall-off-the-bone, add fresh cream and chopped coriander leaves. Switch off the heat.
Let the curry rest for 10 minutes before serving. Serve with soft roti or rice.