Combine the chicken with all the marinade ingredients in a large bowl, stirring to mix and coat well. Cover the bowl, then refrigerate for at least 30 minutes and up to 48 hours.
Place a pan over high heat. Add a splash of spray oil and sear the chicken for 2 ½ minutes on each side or until golden. Do this in batches to prevent steaming the chicken. The chicken will not be cooked at this point. This step is for colour. Remove from the heat and set aside.
Heat the ghee in a large pot over medium-high heat for the sauce, then add the onion and capsicum. Cook, stirring occasionally, for 6 minutes until softened, then add the garlic and ginger and cook, stirring regularly, for 1 minute or until fragrant.
Add the spices and cook for 1 minute, stirring well to allow those flavours to become friends. Add the tomato paste and cook for 4 minutes or until the oil separates.
Add the chicken pieces, the reserved marinade, and the yoghurt to the sauce, then cook for 2 minutes at a gentle simmer to combine the ingredients. Add the stock, bring the mixture to a boil, then reduce the heat to low and simmer for 25 minutes, or until a thick, deep red gravy has formed and the sauce coats a spoon. Feel free to add a splash of chicken stock if the sauce reduces and thickens too much. Season to taste.
Place the rice, water, and ground turmeric in a saucepan over high heat. Bring to a boil, reduce heat to low, cover with a lid, and cook for 12 minutes. Turn off the heat and leave the lid on for 4 minutes. Remove the lid, add coriander (cilantro), and mix well.
Add the cream and most of the chopped coriander. Stir through and cook for 2 minutes to heat through. Remove the chicken tikka masala from the heat and sprinkle with the remaining coriander. Serve the curry and rice in 5x 750ml meal prep containers. Dig in.