Sunflower oil for greasing 1.1kg (21/4lb) sea bass, cleaned and filleted 4 tarragon sprigs 1 lemon, sliced salt and black pepper 2tbsp dry white wine.
Lemon Butter Sauce
150ml (1/4 pint) single cream juice of ½ lemon 45g (11/2oz) butter, melted 1 egg yolk 1tsp plain flour white pepper 1tsp chopped fresh tarragon.
1- Put a large piece of foil on to a baking tray and brush lightly with oil. Put the sea bass on to the foil, tuck 3 of the tarragon sprigs and all but 1-2 of the lemon slices inside the cavity, and sprinkle with salt and black pepper.
2- Season the outside of the fish, and lift up the sides of the foil. Pour the wine over the fish, then seal the foil into a loose parcel. Bake in a preheated oven at 200ْ C (400ْ F, Gas 6) for 30 minutes or until the flesh is opaque, and flakes easily.
3- Meanwhile, make the sauce: whish the cream in a pan with the lemon juice, butter, egg yolk, and flour until mixed. Heat very gently, stirring constantly, until the mixture is thick enough to coat the back of a spoon. Season with salt and white pepper, and stir in the tarragon. Keep warm.
4- Remove the sea bass from the foil and arrange on a warmed serving dish. Pour over the cooking juices. Garnish with the remaining lemon slices and tarragon sprig, and serve at once. Serve the warm lemon butter sauce separately.