Preheat the oven to 400 F and line a baking tray with parchment paper.
Toss the apples with the brown sugar, cinnamon and Skor bits and set aside.
Place the puff pastry sheet on a lightly floured work surface and roll it (if needed) to a 10-inch square. Cut a rectangle that is 4-x-10-inches and place this on the prepared baking tray and brush it with egg wash. Cut a second rectangle that is 4 ½-x-10-inches and return it to the fridge to keep cold. Cut the remaining pastry dough into ½-inch strips. Place the strips on the base of the strudel, on its outside edges, trimming if needed and brushing with egg wash (this creates a frame to hold in the apple filling). Spoon the apples into the centre of this.
Pull the top portion of the pastry from the fridge and make slits at ½-inch intervals. Place this over the apples, brush with egg wash and sprinkle with caster sugar. Bake the jalousie for 10 minutes at 400 F and then reduce the oven temperature to 375 F and bake for an additional 20 to 25 minutes, until it is a rich golden brown. Serve the jalousie warm or at room temperature.