The Welsh call sea trout sewin and they come mainly from the fast-flowing rivers of Wales. Their pink flesh and delicate flavour are admirably complemented by the pretty green sauce. If you can’t get the herbs specified use other ones but beware of those like thyme with an overpowering flavour.
Stunning to look at, and easier than you might think to prepare. Go to town on the decoration to make the finished dish as pretty as a picture.
900 g (2 lb) sea trout, cleaned
45 ml (3 tbsp) lemon juice
50 g (2 oz) butter
salt and pepper
1 bunch watercress, trimmed and roughly chopped
100 g (4 oz) fresh spinach leaves, roughly chopped
45 ml (3 tbsp) chopped fresh parsley
30 ml (2 tbsp) chopped fresh chervil
5 ml (1 tsp) chopped fresh dill
150 ml (1/4 pint) mayonnaise
fresh herbs and whole unpeeled cooked prawns, to garnish
1. Place the fish in the centre of a large piece of foil. Add 30 ml (2 tbsp) of the lemon juice, then dot with 25 g (1 oz) of the butter. Season to taste.
2. Seal the foil, weigh the fish and place on a baking sheet. Calculate the cooking time at 10 minutes per 450 g (1 lb) . Bake at 180°C (350°F) mark 4 until tender.
3. Remove the fish from the foil, reserving the cooking liquor, then carefully remove the skin while still warm. Arrange the fish on a serving dish and leave to cool.
4. To make the sauce, put the cooking liquor and the remaining 25 g (1 oz) butter in a saucepan and heat gently. Add the watercress, spinach, parsley, chervil and dill, then cook for 2 – 3 minutes, until softened.
5. Put the sauce in a food processor or blender and work until smooth. Transfer to a bowl and add the remaining lemon juice and season to taste. Leave to cool, then fold in the mayonnaise. Turn into a small serving bowl and refrigerate until required.
6. When the fish is cold, garnish with fresh herbs and whole prawns, if liked. Serve with the herb sauce.