Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
  10      fillet        ed fresh herrings
   2 1/2  cups          Guinness -- (pref. draft)
   5      fluid ounces  vinegar
                        onion cut into rings
                        bay leaves
                        cloves
                        white and black peppercorns
                        salt as required
   1      teaspoon      brown sugar

Preparation:

Wash herring fillets and roll up, starting from the tail. Place in a baking dish and add the stout-and-vinegar mixture. Add all other ingredients. Cover with baking parchment or foil and bake in a moderate oven (about 350F) for 20 minutes. Remove from oven, allow to cool, and serve.