Clean, wash and cut fish into slices.Mix together turmeric powder, kashmiri chilli powder, pepper powder and salt and make it into a fine, thick paste by adding water or lime juice.Marinate the fish pieces in this masala paste and keep it aside for half an hour.Heat coconut oil in a pan and shallow fry the marinated fish on a medium-low flame till it turns golden brown( make sure you flip the fish to cook both the sides).Remove from oil and drain on a tissue paper. Serve hot with steamed rice.