1 whole salmon, sea trout or sea bass, weighing about 2.25kg, scaled if necessary, gutted and trimmed

360ml green mayonnaise

For the court bouillon:

450ml dry white wine

about 3 litres water

1 large onion, sliced

2 carrots, thinly sliced

1 celery stalk, thinly sliced

½ lemon, sliced

a few parsley sprigs

1 bay leaf

12 black peppercorns

4 allspice berries [optional]

salt

Combine all the ingredients for the court bouillon in a fish kettle or in a large roasting tin. Bring to the boil, cover and simmer for 20 minutes.

Place the fish on the kettle rack, or set it on a piece of muslin. Lower the fish into the court bouillon. The fish should be covered with liquid, so add more water if necessary.

Cover and bring back to boiling point, then simmer very gently for 15-20 minutes or until just cooked.

Remove the kettle from the hear and lift the fish, by means of the rack or muslin hammock, out of the court bouillon. Drain well, then transfer the fish to a serving platter and leave to cool slightly.

Gently peel off the skin and pull out the fins.

If salmon has been used, gently scrape off the layer of greyish flesh. Cool completely.

Serve the cooled fish with the green mayonnaise.

For green mayonnaise:

Combine 30g each parsley sprigs and watercrest sprigs in a blender or food processor. Add 3-4 chopped spring onions and 1 garlic clove. Blend until finely chopped. Add 120ml mayonnaise and blend until smooth. Season.