Appelflappen (Turtă de mere olandeze)

Preheat the oven to 350 degrees Fahrenheit.

Peel and core the apples. Then cut them into small cubes and place them into a bowl.

Add 2 tablespoons of sugar (keep 1 tablespoon aside) and the cinnamon to the apples and mix until well combined.

Unfold the puff pastry sheets, sprinkle with a tiny bit of flour, then flatten them with a rolling pin to remove the precut lines. Try to keep a square shape when flattening. Repeat with the second sheet.

Cut the pastry sheets in four squares each. Divide the cut apples over the sheets (place it on half of the sheet in a triangle shape) and fold diagonally.

Cut the edges of the puff pastry evenly if necessary and close them by pushing down with a fork on the edges.

Whisk the egg in a small bowl until smooth. Brush the egg over each appelflap and sprinkle the remaining sugar over them.

Bake the appelflappen in the oven for about 25 minutes, or until golden brown.

When they are done, place them on a baking rack to cool off for at least 15 minutes.