01 - Preheat oven to 400°F. Grease a 9x13-inch baking dish with cooking spray or a light coating of oil.
02 - Arrange frozen tater tots in a single layer across the prepared baking dish. Drizzle evenly with olive oil. Bake for 20 minutes until lightly golden and starting to crisp.
03 - Remove dish from oven. Spread pizza sauce evenly over the partially baked tater tots. Sprinkle with dried oregano, dried basil, and garlic powder.
04 - Top with half of the shredded mozzarella and cheddar cheese. Distribute pepperoni, black olives, diced bell pepper, and red onion across the surface. Finish with remaining mozzarella, cheddar, and grated Parmesan.
05 - Return to oven and bake for 20 additional minutes, or until cheese is fully melted, bubbly, and golden brown with crispy edges.
06 - Let casserole rest for 5 minutes before serving to allow layers to set for easier scooping.