Bring a large pot of salted water to a boil. Add cheese tortellini and cook according to package instructions, about 3-5 minutes. Reserve 1/2 cup pasta water and drain.

Heat olive oil in a skillet over medium-high heat. Sear the thinly sliced beef for 2-3 minutes on each side until browned. Remove and set aside.

Add more olive oil if needed, sauté onions and bell peppers for 3-4 minutes. Add minced garlic and cook for 30 seconds.

Pour in beef broth and Worcestershire sauce, scraping the pan to release any browned bits. Simmer for 2 minutes.

Stir in heavy cream and add provolone cheese gradually, mixing until smooth. Adjust thickness with reserved pasta water if necessary.

Return the beef and tortellini to the skillet, toss gently in the sauce until everything is heated through.

Adjust seasoning to taste, serve hot garnished with parsley and red pepper flakes if desired.