The flavours can be altered according to your preferences and what is in your fridge. A few olives, a little crushed garlic, sliced mushrooms or some julienned vegetables. For these I used semi sun dried tomatoes and baby spinach.
This is the process
Cut each fillet in half and open out to form a thinner piece, place the semi sun dried tomatoes on top
Add some baby spinach leaves and a little black pepper if desired
Cut a sheet of pastry in half and place the fish portion at one end of the pastry.
Fold the sheet over so that the fish is enclosed, press the pastry together. Leave a border of pastry, trim away the excess and then roll the edges of the pastry over. Place on a tray lined with baking parchment. Brush with milk or an egg wash and sprinkle with sesame seeds. Bake in a hot oven (200 deg C) for approximately twenty minutes or until the pastry is puffed, flaky and golden brown.