How to cook
Grate the apples or cut them into very small pieces. If you're using nectarines, crush them finely. Mix them with the walnuts, cinnamon and nutmeg. Transfer them into a pot and put on the stove to stew, adding honey as well.
Lightly grease a baking dish and place 1 sheet of puff pastry in it, making sure it spills out of the dish’s sides. Add the filling and fold the edges on top. Cut the second sheet of puff pastry into thin strips and arrange them in a grid-like pattern on top of the pie.
Smear the pie with beaten egg with a little water. Put it to bake in a preheated 392°F (200 °C) oven until pinking. When cool, sprinkle it with powdered sugar.