Philly Cheesesteak Sliders

1. Sauté Veggies: Heat 1 tbsp olive oil in a large skillet over medium heat. Add sliced onion and bell pepper. Sauté until softened and caramelized, about 8-10 minutes. Remove from skillet and set aside.
2. Cook Beef: Increase heat to medium-high. Add shaved beef to the skillet in a single layer. Cook for 1-2 minutes per side until browned. Season with salt and pepper. Break up the beef with a spatula.
3. Assemble Sliders: Preheat oven to 350°F (175°C). Slice the entire package of Hawaiian rolls horizontally without separating them. Place the bottom halves in a 9x13 inch baking dish.
4. Layer: Layer half of the provolone cheese slices over the bottom buns. Top with the cooked beef, then the sautéed vegetables, and finally the remaining provolone cheese slices. Place the top halves of the rolls over the cheese.
5. Butter Topping: In a small bowl, whisk together melted butter, Worcestershire sauce, garlic powder, onion powder, dried oregano, and red pepper flakes (if using). Brush this mixture evenly over the tops of the slider buns.
6. Bake: Cover the baking dish loosely with foil and bake for 10 minutes. Remove foil and bake for another 5-10 minutes, or until the cheese is melted and bubbly and the tops of the rolls are golden brown.
7. Serve: Let cool for a few minutes before slicing into individual sliders and serving.