Make spice mixture by combining garam masala, coriander, turmeric, cumin, cayenne, and salt.
Combine ½ of spice mixture (reserving the other half), yogurt, 3 cloves minced garlic, and ginger in a medium bowl and mix well. Add chicken and stir to coat. Cover and refrigerate for 6 to 24 hours.
Warm ghee in a large skillet over medium heat. Add onions and saute until soft and translucent, about 5 minutes. Add remaining garlic and cook another minute. Add tomato paste, tomatoes and cardamon pods and remaining spice mixture and bring mixture to a boil. Reduce heat to a simmer and cook 8-10 minutes.
Add cream and cilantro and simmer, stirring occasionally for 30-40 minutes.
Meanwhile pre-heat broiler and line a baking sheet with aluminium foil.
Arrange chicken on a wire rack in a single layer and place on the baking sheet.
Broil chicken until it starts to blacken in spots, about 10 minutes. Don't worry if it isn't cooked through.
Cut chicken into bite sized pieces add to sauce and simmer another 10 minutes. Remove cardamon pods.
Serve immediately with rice.
Recipe by Three Hungry Boys at https://www.threehungryboys.com/2019/04/28/chicken-tikka-masala/