Boil the Potatoes: Cook the peeled potatoes in salted water until soft. Drain and mash them in a bowl.
Make the Filling: Mix the mashed potatoes with soft cheese, grated Parmesan, salt, and black pepper until creamy.
Assemble the Pastry: Roll out the puff pastry on a baking sheet. Spread the potato mixture evenly over half of the pastry. Layer the cooked ham and shredded mozzarella on top.
Fold & Seal: Fold the other half of the pastry over the filling and seal the edges by pressing with a fork.
Apply Egg Wash: Brush the top with the egg wash and sprinkle extra Parmesan cheese for a golden, crispy finish.
Bake: Preheat the oven to 375°F (190°C). Bake for 20–25 minutes or until golden brown and puffed.
Cool & Serve: Let it rest for a few minutes before slicing. Serve warm and enjoy!