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 up to overnight.
02 - Set Instant Pot to Sauté mode. Add 2 tbsp butter and melt. Add diced onions, minced garlic, and ginger paste. Sauté until onions are soft, approximately 3-4 minutes.
03 - Stir in tomato puree, ground cumin, smoked paprika, ground coriander, and cayenne pepper. Cook for 2 minutes, stirring frequently to develop flavors.
04 - Add marinated chicken along with all marinade to the pot. Stir to combine thoroughly with the sauce base.
05 - Secure the lid. Set Instant Pot to Manual or Pressure Cook on High for 8 minutes.
06 - Allow natural pressure release for 10 minutes once cooking completes, then perform quick release for any remaining pressure.
07 - Stir in heavy cream and remaining 2 tbsp butter. Simmer on Sauté mode for 2-3 minutes, stirring until sauce achieves rich, creamy consistency. Adjust salt to taste.
08 - Serve hot, garnished with chopped fresh cilantro. Accompany with basmati rice or warm naan bread.