1 cup plain, full-fat yogurt Greek; with Greek, 2% worked too
4 garlic cloves minced or grated, divided
2 inch piece ginger minced or grated, divided
2 teaspoons kosher salt divided, plus more to taste
2 to 3 tablespoons neutral oil or ghee
2 large yellow onions minced
1 teaspoon cumin seeds
2 1/2 cups small diced fresh tomatoes from 3 to 4 roma tomatoes, or 1 15-ounce can crushed tomatoes
2 tablespoons tomato paste
1 1/2 teaspoons ground turmeric
1 teaspoon garam masala
1 tablespoon ground coriander
1/2 to 1 teaspoon cayenne or mild chile powder such as kashmiri, or to taste
1/2 cup water
Equipment
bowl
large heavy pan with a lid
Directions
Combine chicken thighs with yogurt, half of garlic, ginger, and salt in a bowl and set aside for whatever time you’ve got — you can use them right away, in an hour, or up to a day.
In a large (4 quarts), heavy pan with a lid, heat oil or ghee. Once hot add onions and cumin seeds, cook 5 minutes, until browned at edges. Add remaining ginger and garlic and cook one to two minutes more. Add remaining salt, turmeric, garam masala, coriander, and cayenne or another chile powder cook for two minutes.
Add tomatoes and cook until they begin to break down, 4 minutes. Add tomato paste, cook for another 2 minutes.
Add chicken and yogurt marinade from bowl, plus water, stir to combine, and bring to a simmer, stirring.
Simmer 25 to 30 minutes over low heat, covered, stirring once or twice to ensure everything is cooking evenly.
Chicken is done when it is cooked through and very tender (you can cut a larger chunk in half to check for doneness). Adjust seasoning as needed and serve with rice.