Prepare the dough by mixing flour, sugar, salt, and butter together.
Gradually add cold water and mix until a dough forms.
Prepare the apple filling by peeling, coring, and chopping the apples.
In a bowl, combine chopped apples with lemon juice, cinnamon, sugar, and cornstarch.
Preheat the oven and roll out the dough on a floured surface.
Cut the dough into circles and fill with the apple mixture.
Fold the dough over the filling and crimp the edges to seal.
Brush each empanada with egg wash and make small slits on top.
Bake the empanadas until golden brown and crisp.
Allow them to cool before serving.