Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.

Heat olive oil in a large skillet over medium-high heat. Add the ground beef and cook until browned, breaking it into crumbles as it cooks. Drain excess fat if necessary.

Add the diced onions and bell peppers to the skillet. Sauté for 3-4 minutes until the vegetables soften. Stir in the minced garlic and Italian seasoning, cooking for another minute until fragrant. Remove from heat and let the mixture cool slightly.

On a lightly floured surface, roll out the pizza dough into a large rectangle (approximately 10x14 inches).

Sprinkle half of the mozzarella cheese evenly over the dough, leaving a 1-inch border around the edges.

Spread the beef and vegetable mixture over the cheese layer, then top with the remaining mozzarella.

Starting from the long edge, tightly roll the dough up jelly-roll style. Pinch the seam and the ends tightly to seal the filling inside.

Place the roll seam-side down on the prepared baking sheet. Brush the top and sides generously with the beaten egg.

Cut 3-4 small slits in the top of the bread to allow steam to escape. Sprinkle with fresh parsley.

Bake for 20-25 minutes, or until the crust is deep golden brown and sounds hollow when tapped.

Allow the bread to cool for 10 minutes before slicing into 1-inch rounds. Serve warm with marinara sauce for dipping.