Preheat oven to 400 degrees F. Take out puff pastry, keep folded and set aside.
Peel and dice apples into small chunks.
Place apples, spices, sugar, butter, cornstarch, and lemon juice in a small pot over medium heat.
Stirring occasionally, bring mixture to a boil, allowing filling to thicken, 5 or so minutes.
Once your mixture has thickened and you can see your brown sugar is gooey goodness coating the apples, remove from heat and set aside.
Unfold both puff pastry sheets (you should have 1 1/3 sheets) and cut down vertical center lines so you have 4 long vertical sheets.
Place 2 unused sheets back in the freezer.
Cut one line horizontally through the middle of each sheet so that you are left with 8 rectangles, a top and a bottom.
Crack egg into a dish and beat with a fork to break. This is your "glue."
Spoon 1 heaping tablespoon of filling neatly in a line down the center of one rectangle. Dip your finger in the egg wash and run it along each edge of the rectangle.
Place an unused rectangle on top to cover your mixture. Using a fork, gently crimp by pressing the top layer halfway down into the bottom layer to seal the edges.
Brush egg wash over the entire shell. Using a knife, make 3 tiny slits so the turnover vents and doesn't explode in your oven!
Place on baking sheet and repeat with the next 3. If your surface gets too sticky, sprinkle with flour. If too much filling is popping out of the sides use less, if not enough use more.
Bake 18-20 minutes.
Let cool at least 10 minutes. Serve warm with my caramel sauce over a bed of ice cream!