Chop 2 onions and add to slow cooker with 30g butter
Add 2 tablespoons tomato paste, 2 tablespoons garlic paste, and 2 tablespoons ginger paste to slow cooker
Add 2 tablespoons paprika, 1 tsp cayenne, 2 tablespoons garam masala, 1 tsp cumin, 1 tsp coriander, 2 tsp salt, and dash of black pepper
Pour in one 14 oz can of crushed fire roasted tomatoes and ½ cup (120ml) water
Add 32oz diced chicken breast to slow cooker
Cook on High for 2-3 hours or Low for 3-4 hours
Blend the mixture, optionally adding 1 tablespoon chicken bouillon and 1 tablespoon sugar or zero calorie sweetener
Stir in 250g plain nonfat greek yogurt or skyr and 30g butter
Cook basmati rice with ~630ml water and divide evenly across 7 servings
Serve butter chicken over rice or with fresh naan if preferred