Trim the fillet by removing the bones and then cutting away the thin (belly) side and the tail end so that you are left with a centre cut about 3 in / 7.5 cm. wide and 10 in / 25.5 cm. long. (The trimmings can be used for other things - smoked haddock tartare, omelette filling or kedgeree.) Cut the fish vertically into slices just under ¼ in / 0.5 cm. thick. Lay on a platter. Brush with hazelnut oil, sprinkle with a little salt and pepper, and leave for 2–3 hours. About 30 minutes before serving, brush with lime juice and a little rum or whisky, if liked. To serve, arrange five or six pieces on a plate with a few small salad leaves. I often serve it with pickled samphire.