Marinate the chicken: mix yoghurt, lemon juice, turmeric, red chilli powder, and garam masala. Coat the chicken well and marinate for at least 1 hour.
Pan-fry or grill the marinated chicken on high heat until lightly charred and cooked through, about 5-6 minutes per side. Set aside.
Melt butter in a pan. Saute onions until soft. Add ginger-garlic paste, cook 2 minutes. Add tomato puree and cook until butter separates — about 10 minutes.
Blend soaked cashews to a smooth paste. Add to the gravy with red chilli powder. Stir and simmer 5 more minutes. Strain the sauce for a smoother texture.
Add the cooked chicken into the gravy. Stir in fresh cream and crushed kasuri methi. Simmer on low heat for 10 minutes.
Add a pinch of sugar to balance the acidity. Garnish with cream and coriander. Serve with naan or rice.