Preheat oven to 250C (480F).

Take 2 large pieces of foil. Place lemon slices in the center of each. Top each with fish and butter and season well. Fold the foil to wrap and seal the fish. Repeat with the second parcel.

Bake for 10 – 12 minutes or until the fish is cooked to your liking.

To serve, divide leaves between two plates. Top each with fish and lemon slices and drizzle over the juices from the bag.