Prepare the Steak: Lay the flank steak flat and pound it to about ¼-inch thickness.
Make the Filling: In a bowl, combine breadcrumbs, Parmesan, minced garlic, parsley, olive oil, salt, and pepper.
Assemble the Rolls: Spread the filling evenly over the steak slices. Optionally, lay a slice of prosciutto on top. Roll each steak tightly and secure with butcher’s twine or toothpicks.
Sear the Rolls: Heat olive oil in a pan over medium heat. Sear the beef rolls on all sides until browned. Remove and set aside.
Prepare the Sauce: In the same pan, sauté onions and garlic until fragrant. Add crushed tomatoes, oregano, red pepper flakes, wine (if using), sugar, salt, and pepper. Simmer for 5 minutes.
Cook the Braciole: Add the steak rolls back into the sauce. Cover and simmer on low heat for 1.5 hours, turning occasionally.
Serve: Remove the twine or toothpicks. Serve hot with pasta or crusty bread, garnished with fresh basil.