Peel, slice, and boil the apples for 30 minutes. Mix the Pecorino Toscano DOP, the mascarpone, and the sugar in a bowl until you have a whipped mixture. Add the egg yolks, the starch, and whip for 10 minutes. Add the flour, being careful to knead slowly, and, then, the egg whites, previously whipped. Apply the shortcrust on the bottom of a cake mold. Lay the apple slices so that they cover the entire surface of the dough and pour the Pecorino Toscano mix until it covers it. Bake in the oven at 120/140 °C for 35/40 minutes. When the pie is ready, decorate it with powdered sugar and serve.