Preparation: Preheat your oven to 400°F (200°C). Line a large baking sheet with parchment paper to prevent sticking.
Roll the Dough: On a lightly floured surface, roll the pizza dough into a large rectangle (approximately 10x14 inches).
Layer the Fillings: Lay the ham slices evenly over the dough, leaving a 1-inch border around the edges. Sprinkle the mozzarella and Parmesan cheese generously over the ham.
Roll It Up: Starting from one long side, roll the dough up tightly into a log. Pinch the long seam and the ends firmly with your fingers to seal in the cheese.
The Golden Finish: Place the stromboli seam-side down on the prepared baking sheet. Brush the top and sides with the egg wash. Drizzle the melted butter over the top and sprinkle with garlic powder and Italian seasoning.
Vents & Baking: Cut 3 or 4 small slits across the top to allow steam to escape. Bake for 20–25 minutes until the crust is a deep, burnished golden brown.
Rest & Slice: Let the stromboli rest for at least 5 minutes before slicing into thick rounds. This allows the cheese to set so those beautiful cheesy spirals stay intact!