01 -
Preheat the oven to 400°F and line a baking sheet with parchment paper or lightly grease the sheet.
02 -
Heat olive oil in a skillet over medium heat. Sauté the green bell pepper and onion for 4 to 5 minutes until softened.
03 -
Add sliced beef to the skillet and cook for 3 to 4 minutes until just heated through. Season with garlic powder, salt, and black pepper. Remove from heat and let cool slightly.
04 -
On a lightly floured surface, roll out pizza dough into a rectangle approximately 10 inches by 14 inches.
05 -
Distribute the beef, bell pepper, and onion mixture evenly over the center of the dough, leaving a 1-inch border on all sides.
06 -
Sprinkle shredded mozzarella and provolone cheeses evenly over the filling.
07 -
Roll up the dough firmly from the long side into a tight log. Pinch the seams and ends to seal. Place the roll seam-side down on the prepared baking sheet.
08 -
Brush the surface of the stromboli with the beaten egg for a golden finish.
09 -
Make 3 to 4 small slits along the top to vent steam. Bake for 20 to 25 minutes or until golden brown.
10 -
Allow to cool for 5 to 10 minutes before slicing. Serve warm, with dipping sauce if desired.