In a large or medium bowl, add 1.5 cups yogurt, 3 garlic cloves (minced), 2 teaspoons minced ginger, 2 teaspoons ground turmeric, 1 teaspoon cumin, 1 teaspoon coriander, 1 teaspoon garam masala, ½ teaspoon salt, and 2lbs cubed chicken breasts. If you do not have skewers, slice chicken breasts in half. Cover with clear wrap and place in the refrigerator. Chill for 4+ hours.
Heat butter (or ghee) in a large heavy pot over medium heat until melted. Add 1 small onion (chopped) and cook until translucent, about 5-6 minutes.
Then add 2 garlic cloves (mined), 2 teaspoons fresh ginger (minced), and remaining spices (2 teaspoons ground turmeric, 1 teaspoon ground coriander, 1 teaspoon ground cumin, 1 teaspoon garam masala). Stir together with onions and cook for 30-60 seconds.
Add ¼ cup tomato paste and cook until the bottom of the pan begins to darken, about one minute.
Add 28-oz canned crushed tomatoes (with juice) and bring to a boil, then reduce heat and simmer. Stir often and scrape up browned bits from the bottom of the pot until sauce thickens (about 8-10 minutes)
Add 2 cups heavy cream and ¼ cup chopped cilantro. Season with salt to taste. Let the sauce simmer with lid on. Stir occasionally.
If Using Skewers: Place chicken pieces on a skewer stick and grill until chicken starts to blacken/char in spots (it will likely not be cooked through) for 10 minutes.
If Grilling Without Skewers: If you don't have skewer sticks/grill, then place chicken breasts on the grill until chicken starts to blacken/char in spots. Once done, transfer to a cutting board and let rest for 5-10 minutes. Then cut into 1-inch cubes. This is our preferred method.
If Using Oven: Place chicken on a rimmed baking sheet and cook under a high broil until chicken as blackened/char.
Add chicken to the sauce and let simmer for 10-15 minutes so that the chicken can cook through.
Serve warm with basmati rice, naan bread, and roasted cauliflower. Garnish with ¼ cup fresh cilantro.
