Sear chicken thighs skin-side down in 2 tablespoons of oil until golden-brown and set aside.
Sauté onions, garlic, ginger, and red pepper in remaining oil until soft.
Blend the cooked vegetable mixture until smooth and return the purée to the pan.
Cook the purée over low heat for 10 minutes.
Stir in tomato purée, curry paste, and dry spices then cook for 5 minutes.
Return chicken to the sauce and simmer for 20 minutes.
Toast whole spices in oil within a saucepan then stir in the rice.
Add 650ml water and salt then simmer covered on low heat for 30 minutes.
Fluff the rice with butter using a fork before serving.
Plate the rice and curry then garnish with chilli and coriander.