Sautéed herring with a sweet and sour relish

At an early age I asked my father to name his favourite fish, and the answer was, unhesitatingly, ‘fresh herring in oatmeal, preferably for breakfast’. This obviously registered, because I still regard this delicious fish with awe. Reading Jane Grigson’s marvellous Fish Cookery only reinforced this opinion early in my career. Combine this predilection with the existence o