Evenly season the chicken with salt and turmeric; set aside for 15 minutes.
Heat the oil in a large frying pan, wok or kadhai over medium heat. Cook the onions in the hot oil until browned, about 5 minutes. Add the chicken and cook until browned, about 5 minutes more. Stir the peppers and chilllies into the chicken; continue cooking another 5 minutes.
Grind the cumin seed, coriander seed, black peppercorns, cinnamon, cloves, cardamom pod and fennel seed into a coarse powder; sprinkle over the mixture in the frying pan. Add the water, coconut milk powder, chilli powder and salt. Cook until the chicken is tender, about 30 minutes. If the curry is too wet, cook on high until the moisture evaporates. Garnish with coriander and serve hot.
Coconut milk powder
Is available at some supermarkets and Indian/South Asian stores.