Ingredients:
2 lb (1 kg) chicken thigh fillets, cut into 1 inch (2.5-cm) pieces
1/2 cup (4 fl oz/125 ml) buttermilk
2/3 cup (5 fl oz/150 ml) vegetable oil and melted unsalted butter combined
1-inch (2.5-cm) cinnamon stick
3 green cardamom pods, cracked
3 whole cloves
1 teaspoon powdered asafoetida
5 yellow (brown) onions, chopped
2 1/2 tablespoons crushed fresh ginger
2 1/2 tablespoons crushed gailic
3-4 tablespoons chili powder
2 1/2 tablespoons ground coriander
4 teaspoons ground turmeric
salt to taste
8 tomatoes, chopped
1 cup (1 1/2 oz/45 g) chopped fresh cilantro (coriander)
2 tablespoons crushed black peppercorns
18 fresh curry leaves
steamed basmati rice

Method:
In a glass or ceramic bowl, combine chicken and butternilk, and mix well. Place in refrigerator to marinate while preparing sauce.

In a large, heavy saucepan or karhai, heat oil and butter micture oven medium heat. Add cinnamon, cardamon and cloves and cook until fragrant, about 30 seconds. Immediately stir in asafoetida, then add onions.

Cook onions, uncovered, stirring often, until dark golden brown, 10-15 minutes. Add ginger and garlic and cook, stirring, for 1 minute.

Add chili powder, coriander, turmeric and salt to tatse, and stir until fragrant, about 1 minute. Add tomatoes and cook, uncovered, stirring occasionally, until tomatoes soften and sauce thickens slightly, 10-15 minutes

Stir in chicken and buttermilk and cook, stirring often. until chicken is cooked through. 5-10 minutes. Add cilantro, peppercorns and curry leaves and mix well.

Serve with steamed rice.

Chicken Chettinad Recipe