Chicken tikka masala

INGREDIENTS

For the chicken marinade:

• 28 oz (800g) boneless and skinless chicken thighs cut into bite-sized pieces (I used one pork tenderloin)
• 1 cup plain yogurt
• 1 1/2 tablespoons minced garlic
• 1 tablespoon ginger
• 2 teaspoons garam masala
• 1 teaspoon turmeric
• 1 teaspoon ground cumin
• 1 teaspoon Kashmiri chili (or 1/2 teaspoon ground red chili powder) (I used cayenne)
• 1 teaspoon of salt

For the sauce:

• 2 tablespoons of vegetable/canola oil
• 2 tablespoons butter
• 2 small onions (or 1 large onion) finely diced
• 1 1/2 tablespoons garlic finely grated
• 1 tablespoon ginger finely grated
• 1 1/2 teaspoons garam masala
• 1 1/2 teaspoons ground cumin
• 1 teaspoon turmeric powder
• 1 teaspoon ground coriander
• 14 oz (400g) tomato puree (tomato sauce/Passata)
• 1 teaspoon ground red chili powder (I used cayenne and it was pretty spicy)
• 1 teaspoon salt
• 1 1/4 cups of heavy or thickened cream 
• 1 teaspoon brown sugar (a little too sweet; add to taste instead)
• 1/4 cup water if needed
• 4 tablespoons Fresh cilantro or coriander to garnish

INSTRUCTIONS

• In a bowl, combine chicken with all of the ingredients for the chicken marinade; let marinate for 10 minutes to an hour (or overnight if time allows).
• Heat oil in a large skillet or pot over medium-high heat. When sizzling, add chicken pieces in batches of two or three, making sure not to crowd the pan. Fry until browned for only 3 minutes on each side. Set aside and keep warm. (You will finish cooking the chicken in the sauce.)
• Melt the butter in the same pan. Fry the onions until soft (about 3 minutes) while scraping up any browned bits stuck on the bottom of the pan. 
• Add garlic and ginger and sauté for 1 minute until fragrant, then add garam masala, cumin, turmeric and coriander. Fry for about 20 seconds until fragrant, while stirring occasionally.
• Pour in the tomato puree, chili powders and salt. Let simmer for about 10-15 minutes, stirring occasionally until sauce thickens and becomes a deep brown red colour.
• Stir the cream and sugar through the sauce. Add the chicken and its juices back into the pan and cook for an additional 8-10 minutes until chicken is cooked through and the sauce is thick and bubbling. Pour in the water to thin out the sauce, if needed.
• Garnish with cilantro (coriander) and serve with Naan bread