01 - Preheat oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish.
02 - Spread the bagel pieces evenly along the bottom of the prepared baking dish.
03 - Drizzle half of the pizza sauce over the bagels. Sprinkle with half of the shredded mozzarella and Parmesan cheese.
04 - Distribute half of the pepperoni, olives, diced bell pepper, and sliced red onion over the cheese. Sprinkle with half of the Italian herbs.
05 - Repeat the layering process with the remaining sauce, cheeses, toppings, and herbs to form a second layer.
06 - Cover the dish loosely with aluminum foil and bake for 20 minutes.
07 - Remove the foil and continue baking for an additional 10 minutes, until the cheese is melted and golden.
08 - Allow to cool for 5 minutes before sprinkling with fresh basil or parsley if desired. Serve warm.