Preheat your oven to 350˚.
Place bottom half of slider rolls in baking dish. Spread half of the pizza sauce across them. Top with bell pepper, pepperoni, olives, and mozzarella. Spread the remaining sauce over everything and close the sliders.
In a small bowl mix together Parmesan, olive oil, vinegar, butter, oregano, garlic and red pepper flake.Drizzle over the sliders.
Cover with aluminum foil and bake for 30 minutes or until the cheese is completely melted.