Preheat the oven to 200°C.

Unroll one sheet of puff pastry onto a chopping board, keeping it on the parchment paper it comes with as this can go straight into the oven. Using a sharp knife, cut the pastry into thirds lengthways, then cut across the middle to create 6 equal squares.

Divide half of the shredded chicken between three of the pastry squares. Spoon around 2–3 tbsp of creamy mushroom soup over each, then season with salt and pepper.

Place the remaining three pastry squares on top to create three bakes. Before sealing them, gently slide the middle bake down so it sits corner-to-corner with the other two. This creates enough space between the bakes to crimp the edges.

Use the back of a fork to press firmly around the edges of each bake, sealing the filling inside. Using a sharp knife, lightly score diagonal lines across the top of each bake in both directions to create a diamond pattern, being careful not to cut all the way through the pastry.

Slide the bakes, still on their parchment paper, from the chopping board onto a large baking tray. Repeat with the second sheet of pastry and the remaining filling to make 6 bakes in total.

Whisk the egg, then brush over the tops of all six bakes.

Bake for 20 minutes, or until the pastry is puffed, crisp and golden.