01 - In a large bowl, combine ground beef, Italian seasoning, garlic powder, salt, and black pepper. Mix gently until evenly incorporated, then shape into 4 equal-sized patties.
02 - Heat olive oil in a skillet or grill pan over medium-high heat. Cook the patties for 4 to 5 minutes per side, or until fully cooked through and juices run clear.
03 - Preheat the oven broiler to high. Place the bottom halves of the burger buns on a baking sheet, cut side up.
04 - Spread 1 tbsp of pizza sauce onto each bun bottom. Place one cooked patty on top of each sauced bun.
05 - Spoon another tbsp of pizza sauce over each patty. Layer with shredded mozzarella, pepperoni slices, thinly sliced red onion, and bell pepper strips.
06 - Place the baking sheet under the broiler for 1 to 2 minutes, watching closely, until the cheese is bubbly and fully melted.
07 - Remove from the oven. Garnish with fresh basil leaves or red chili flakes if desired. Top with the remaining bun halves and serve immediately with extra pizza sauce for dipping.