Pre-heat the oven to gas mark 6, 400°F (200°C).

Wash the fish thoroughly and pat it dry with kitchen paper.

Lightly oil a sheet of aluminium foil and place the fish on this.

Lightly season the inside of the belly and tuck in 2 slices of lemon and 2 sage leaves.

Now season all over the outside and cover the fish with the remaining slices of lemon in an overlapping line along the body, with the 2 remaining sage leaves tucked between the slices in the middle.

Bring up the sides of the foil, add 2 tablespoons of vermouth or white wine, then fold and crimp the foil into a loose parcel. Bake in the oven for about 30 minutes, or until the fish is just cooked.

Using two fish slices or spatulas, carefully lift the bass on to a warmed serving platter.

Pour the cooking juices all over and serve immediately. Hand the sauce separately.