In a mixing bowl, combine the ground beef, breadcrumbs, grated Parmesan cheese, pizza sauce, dried oregano, salt, and pepper. Mix until well combined.
Divide the mixture into four equal portions and shape them into burger patties.
Preheat your frying pan or grill over medium-high heat. Cook the burger patties for about 4-5 minutes on each side or until they reach your desired level of doneness.
During the last minute of cooking, place a generous amount of mozzarella cheese on each patty and cover with a lid or foil to melt the cheese.
While the patties are cooking, you can toast your hamburger buns in a toaster or on the grill.
Assemble your pizza burgers by placing a patty on the bottom half of each bun. Top with pepperoni slices, bell peppers, black olives, and red onions.
Complete your burger with the top bun, and your pizza burger is ready to be devoured!