In a large bowl, combine plain yoghurt, minced garlic, grated ginger, spices, and 2 tablespoons of vegetable oil to create a rich marinade. Add the chicken thighs, ensuring they're well coated. Cover the bowl with plastic wrap and refrigerate for at least 3 hours, but for optimal flavor, marinate overnight if possible.

Heat a large pan over high heat and add 2-3 tablespoons of vegetable oil. Once the oil is smoking, carefully add the marinated chicken pieces one at a time, cooking for about 4-5 minutes per side until nicely charred and golden brown. Remove the chicken from the pan and set aside while you prepare the sauce.

In the same pan, reduce the heat to medium and sauté the finely chopped onion and a pinch of salt in the leftover oil until the onions soften and turn golden, roughly 7-8 minutes. Add minced garlic and paprika, cooking for an additional minute until fragrant. Stir in the spices, followed by the tomato passata, allowing them to meld beautifully for approximately 15 minutes.

Using a stick blender, carefully puree the sauce in the pan until completely smooth, ensuring no chunks remain for that lush texture characteristic of Chicken Tikka Masala.

Stir in the cream and an optional tablespoon of butter or ghee, allowing the ingredients to incorporate fully. Return the cooked chicken to the sauce, letting everything simmer on low heat for another 10-15 minutes until the chicken is fully cooked through.

To serve your Chicken Tikka Masala, ladle over fluffy Basmati rice, and consider garnishing with fresh coriander for a pop of color.