When making the Scottish soused herring you can use malt vinegar and water in equal parts, which is authentic but tends to make the dish very forceful, or substitute a mixture of dry white wine and white wine vinegar.
Alternatively you can use equal parts dry cider and cider vinegar. This is not classically Scottish, but makes an excellent marinade just the same. Unless you feel up to the task, have your fishmonger fillet the herrings for you
First make the marinade: put the vinegar and the wine in a pan with all the other ingredients. Bring to the boil, lower the heat and simmer gently for 20–30 minutes. Remove from the heat and leave to cool completely.
Arrange the herring fillets skin-side down in a flameproof roasting pan, pour over the marinade and slowly bring it to the boil on the hob. Immediately remove from the heat and leave to cool.
To finish the dish, blanch the carrot sliced in boiling salted water for 2–3 minutes, then refresh them in cold water and drain.
Arrange the cooled fish fillets on a serving plate and spoon over some of the marinade. Scatter the carrot slices over the fish and arrange the rings of onion on top. Garnish with some flatleaved parsley.
© 1998 Alastair Little and Richard Whittington estate. All rights reserved.