Short Summary to prepare Chicken Tikka Masala at home ~The first step is to marinate the chicken pieces with spices mixed in yogurt. Into a bowl add yogurt, red chili powder, crushed cumin seeds, black pepper crushed, coriander powder, garam masala powder, ginger garlic paste, salt, mustard oil, and lemon juice. Mix these well and dip the chicken pieces into this marinade. Keep it marinated for 30 minutes minimum.Next, after 30 minutes fry these marinated chicken pieces into a frying pan in some oil. Fry both sides until slightly turns golden brown in color and keep aside.To prepare chicken tikka masala gravy we need to first fry the finely chopped onions in some oil. Once these onions turn translucent next add the ginger garlic paste and stir fry few minutes. Next, add tomato puree and stir and cook for 2 minutes. Then add the spices like red chili powder, some turmeric powder, salt, crushed cumin seeds, coriander powder, and mix. Stir and cook few minutes and then add the leftover marinade along with some water. Mix well then add the pan-fried chicken tikka masala into it and mix. Mix well and continue to cook for a few minutes.At this point half and half cream or if using thick cream then add a little extra water to adjust the thickness of the gravy. Mix well and then add dried fenugreek leaves crushed by hands, sprinkle some garam masala, and finely chopped coriander leaves. Give these a nice mix. Cook a few more minutes. You may cover this up or just open cook a few minutes and it should be done.