In a large bowl, combine ground beef, Worcestershire sauce, mayonnaise, garlic powder, 2 tablespoons olive oil, 1 teaspoon salt, and ½ teaspoon pepper. Mix well.
Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add the beef mixture and cook, breaking it up with a spoon, until browned, about 8-10 minutes.
Add the onion and bell pepper to the skillet. Cook, stirring occasionally, until softened, about 5-7 minutes.
Stir in the beef broth, remaining 1 teaspoon salt, and remaining ½ teaspoon pepper. Bring to a simmer and cook for 2-3 minutes, or until the liquid has reduced slightly.
Divide the beef mixture among the toasted hoagie rolls. Top each with 2 slices of provolone cheese.
Place the filled rolls under the broiler for 1-2 minutes, or until the cheese is melted and bubbly.
