Bring a large pot of salted water to a boil. Cook the pasta according to package directions until al dente (usually 8-10 minutes). Drain and set aside.

While the pasta cooks, pat the sliced steak dry and season with 1/2 tsp salt and 1/4 tsp pepper. Heat olive oil in a large skillet over high heat. Add the steak in a single layer and sear for 1-2 minutes per side until browned but not cooked through. Remove to a plate.

In the same skillet over medium heat, add the sliced onion and bell pepper. Cook for 6-8 minutes, stirring occasionally, until softened and lightly caramelized. Add the garlic and Worcestershire sauce, cook for 1 more minute until fragrant.

Push vegetables to the side of the skillet. Add butter to the cleared space and melt. Whisk in flour and cook for 1 minute. Gradually whisk in the warm milk and beef broth until smooth. Bring to a simmer, stirring constantly, until slightly thickened, about 3-4 minutes.

Remove skillet from heat. Stir in 1 cup of the shredded provolone and all the Parmesan until melted. Season with remaining salt and pepper. Add the drained pasta and seared steak (with any juices) to the skillet, gently tossing to coat everything in the sauce.

Preheat oven to 375°F (190°C). Transfer the pasta mixture to a greased 9x13 inch baking dish. Top evenly with the remaining 1 cup of shredded provolone. Bake for 15-20 minutes, until the cheese is melted, bubbly, and golden in spots.

Remove from oven and let rest for 5 minutes. Sprinkle with chopped fresh parsley. Serve hot directly from the baking dish.