Bring a large pot of salted water to a boil. Add cheese tortellini and cook according to package directions until al dente. Drain and drizzle with olive oil to prevent sticking. Set aside.

Thinly slice the beef against the grain. For easier slicing, partially freeze the meat for 15-20 minutes first.

Heat 1-2 tablespoons olive oil in a large skillet over medium-high heat. Add steak slices in a single layer, working in batches if needed, and sear for 2-3 minutes on each side until nicely crusted. Remove and set aside.

In the same skillet, add more olive oil if needed. Add sliced onions, bell peppers, and minced garlic. Sauté over medium heat until tender and caramelized, about 5-7 minutes. Season with salt, pepper, and optional red pepper flakes.

Pour in 1 cup beef broth to deglaze the pan, scraping up any flavorful bits. Stir in 2 tablespoons tomato paste and 1 tablespoon Worcestershire sauce.

Lower heat to medium-low and stir in 1/2 cup heavy cream. Gradually add shredded provolone cheese, stirring continuously until melted and smooth. Adjust seasoning as needed.

Return seared steak to skillet with sauce and vegetables. Gently fold in cooked tortellini, ensuring every piece is coated with sauce.

Let mixture simmer for 2-3 minutes to allow flavors to meld together.

Remove from heat and garnish with freshly chopped basil or parsley. Serve immediately while hot.