Preheat the oven to 375°F (190°C) with the rack in the middle position.

Slice the Italian sub rolls in half lengthwise, leaving them hinged at the bottom. Place cut side up on a baking sheet.

Melt unsalted butter in a saucepan over low heat, then mix in garlic powder, onion powder, dried oregano, dried basil, red pepper flakes, salt, and black pepper.

Brush the cut sides of the rolls generously with the seasoned butter mixture.

Layer deli-sliced salami, ham, and pepperoni on the bottom half of each roll.

Add deli-sliced mozzarella and provolone cheese on top of the meats.

Sprinkle grated Parmesan cheese over the cheese layers.

Distribute roasted red peppers, sliced black olives, banana peppers, and fresh basil leaves over the cheese.

Bake for 10-12 minutes until cheese is melted and bubbly, and the bread is crispy and golden.

Let cool for about a minute, slice into portions, and serve warm.