Cheesesteak Garlic Parmesan Bread (Loaded and Cheesy)

Ingredients

• 1 large Italian or French bread loaf, about 14-16 oz (400-450 g)
• 6 tablespoons (85 g) unsalted butter, softened
• 4 cloves garlic, finely minced
• 1/3 cup (30 g) finely grated Parmesan cheese
• 1 tablespoon chopped fresh parsley, plus more for serving
• 1/2 teaspoon Italian seasoning
• 1/4 teaspoon kosher salt
• 1/4 teaspoon black pepper
• 1 tablespoon olive oil
• 1 medium yellow onion, thinly sliced
• 1 green bell pepper, thinly sliced
• 1 lb (450 g) shaved ribeye or very thinly sliced sirloin
• 1 teaspoon Worcestershire sauce
• 1/2 teaspoon kosher salt, plus more to taste
• 1/2 teaspoon black pepper
• 6 slices provolone cheese
• 1 cup (115 g) shredded low-moisture mozzarella