Preheat oven to 400 degrees F, with a pizza stone or baking sheet inside.
Roll out pizza dough into a large thin rectangle (about 18’’x12’’)
Season dough: Spread with a thin layer of olive oil over the top and sprinkle generously with garlic powder, Italian seasoning, crushed red pepper, and ¼ cup fresh grated parmesan cheese.
Layer deli meats and cheeses: Leaving a 1’’ border around the edge of the dough, layer ham slices, slightly overlapping (like roof shingles) across the top. Repeat with Mozzarella slices, then pepperoni, provolone, and salami. Sprinkle oregano over the top.
Roll up: Fold the long edge of the dough closest to you over the fillings a few inches. Roll/fold the dough away from you to form a log. When you near the end edge of the dough, stop, and pull that dough up and over, towards you. Pinch together to the ends and fold them under, to seal the roll.
Bake: Place Stromboli, seam side down, on a piece of parchment paper. Brush outside of dough with egg wash. Make 3-4 slits on top, for steam to escape. Sprinkle remaining parmesan on top. Bake for 25 minutes on pizza stone or parchment on prepared baking sheet. Remove from oven and use a paper towel to blot excess grease away, if needed.
Rest for 10-15 minutes before slicing.
Serve warm or at room temperature, with marinara or pizza sauce on the side, for dipping.