Start by pureeing the canned apple pie filling in a bowl. Add sugar and cinnamon to enhance the flavor, blending until smooth.

Lay one sheet of frozen shortcrust pastry on a lightly floured surface. Spread a generous layer of the apple filling over it. Place the second pastry sheet on top, pressing the edges together. Brush the top with a beaten egg and sprinkle with sugar granules if desired.

Wrap the assembled pastry tightly in plastic wrap and place it in the freezer for at least 1 hour.

Preheat your oven to 180°C (350°F).

Remove the pastry from the freezer and unwrap it. Slice it into fry shapes. Arrange on a lined baking tray, ensuring they are spaced apart. Bake for 15-25 minutes, or until golden brown and crispy.

In a medium saucepan, combine caster sugar and water over medium heat. Stir until the sugar dissolves and bring to a simmer. Cook until light golden, then add heavy cream, salt, and butter, stirring until smooth.

Let the apple pie fries cool slightly, then serve warm drizzled with the homemade salted caramel sauce.