01 - Combine chicken pieces with all marinade ingredients in a large bowl. Mix thoroughly to coat, cover, and refrigerate for at least 1 hour, or overnight for deeper flavor penetration.
02 - Set Instant Pot to Sauté mode. Add 2 tbsp butter and allow to melt. Add diced onions, minced garlic, and ginger paste. Sauté until onions are soft and translucent, approximately 3-4 minutes.
03 - Stir in tomato puree, ground cumin, smoked paprika, ground coriander, and cayenne pepper. Cook for 2 minutes, stirring constantly to prevent sticking and allow spices to bloom.
04 - Add marinated chicken along with all marinade liquid to the pot. Stir well to incorporate chicken with the spiced tomato base.
05 - Secure the lid and set steam release valve to sealing position. Select Manual/Pressure Cook on High for 8 minutes.
06 - Allow natural pressure release for 10 minutes once cooking completes. Turn steam release valve to venting position to release any remaining pressure.
07 - Switch Instant Pot back to Sauté mode. Stir in heavy cream and remaining 2 tbsp butter. Simmer for 2-3 minutes, stirring continuously until sauce thickens and becomes glossy. Season with salt to taste.
08 - Transfer to serving dish and garnish generously with chopped fresh cilantro. Serve immediately over basmati rice or alongside warm naan bread.