Preheat your oven to 375°F (190°C). In a skillet over medium heat, cook the ground beef or sausage until browned. Drain any excess grease. Stir in pizza sauce, Italian seasoning, and a pinch of salt and pepper. Let it simmer for 2–3 minutes. Spread the meat mixture evenly into a greased 9×13 inch casserole dish. Sprinkle half of the mozzarella, cheddar, and pepperoni over the meat mixture. Arrange frozen tater tots in a single layer on top. Bake uncovered for 30 minutes. Remove from oven, top with the remaining cheese and pepperoni, and return to the oven for another 5–10 minutes, or until cheese is melted and bubbling. Let it rest for 5 minutes before serving.