Instructions:

In a large skillet, cook the ground beef, onion, and green pepper over medium heat until the beef is no longer pink. Drain any excess grease.
Stir in the pizza sauce and Italian seasoning, and simmer for 5 minutes.
Add the mini pepperoni slices and cook for an additional 2 minutes.
Spoon the mixture onto the bottom half of each hamburger bun and sprinkle with mozzarella cheese.
Place the top half of the bun on top and serve hot.