Step 1: Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.
Step 2: On a lightly floured surface, roll out the thawed puff pastry sheet to about a 10x12 inch rectangle. Transfer it to the prepared baking sheet.
Step 3: In a small bowl, whisk together mayonnaise, red wine vinegar, dried oregano, garlic powder, salt, and pepper. Spread this mixture evenly over the puff pastry, leaving a 1/2-inch border.
Step 4: Layer the provolone cheese over the mayonnaise mixture. Then, evenly arrange the salami, pepperoni, and ham over the cheese.
Step 5: Sprinkle the thinly sliced red onion and banana peppers (if using) over the meats.
Step 6: Carefully fold one long side of the puff pastry over the filling, meeting the other long side. Pinch the edges firmly to seal completely, creating a log. You can also fold the short edges to meet in the center and then fold in half, creating a more compact rectangle.
Step 7: Brush the top of the pastry log with the egg wash and sprinkle generously with grated Parmesan cheese.
Step 8: Bake for 20-25 minutes, or until the pastry is golden brown and puffed, and the cheese is melted and bubbly. Ensure the bottom is cooked through.
Step 9: Remove from the oven and let cool for 5-10 minutes before slicing into squares or rectangles using a sharp knife and serving warm.