Chausson aux Pommes (French Apple Turnover)

Instructions

1. Melt the butter in a wide skillet over medium heat. Add the apples, sugar, lemon juice, cinnamon and salt and cook 10 to 12 minutes, stirring, until the apples are soft but still hold their shape and the liquid has thickened.
2. Cool the filling completely, at least 30 minutes; warm filling melts the pastry. Heat the oven to 400 F (200 C) and line a baking sheet with parchment.
3. Roll the puff pastry on a lightly floured surface to about 1/8 inch (3 mm) thick. Cut six 5-inch (13 cm) circles.
4. Brush a rim of water around half of each circle, add about 3 tablespoons of filling on one half, and fold the other half over. Press the edges firmly and crimp with a fork.
5. Place on the sheet, chill 15 minutes, then brush the tops with the beaten egg. Score three or four shallow curved lines in the top with the tip of a knife without cutting through, and sprinkle with sugar.
6. Bake 22 to 25 minutes, until puffed and deep golden. Cool on a rack at least 10 minutes before serving.