Combine the oil with all the other ingredients up to and including the sesame seeds. Rinse the fish (inside and out) in cold water, pat dry. Rub the marinade into the fish, inside and out. Place the reserved lemongrass and kaffir lime leaves inside the fish, cover and marinate in the fridge for at least 2 hrs.
Combine half of the raspberries with all the other ingredients up to and including the lemongrass, season. Add the remainder of the raspberries and the coriander just before serving.
Salt the fish, grill over/on a medium heat (approx. 200 °C for approx. 7 mins. on each side. Remove the lemongrass and kaffir lime leaves, serve with the raspberry salsa.