Bring a large pot of salted water to a boil. Add the tortellini and cook according to package instructions until al dente. Drain and set aside.

In a skillet over medium heat, melt 1 tablespoon of butter. Add the sliced ribeye, bell pepper, onion, and garlic. Cook until the beef is browned and the vegetables are tender, about 5-7 minutes. Remove from heat.

In the same skillet, melt the remaining tablespoon of butter over medium heat. Whisk in the flour and cook for 1 minute. Gradually add the milk, whisking continuously until the mixture thickens, about 5 minutes.

Stir in the provolone cheese, Italian seasoning, salt, and pepper until the cheese is melted and the sauce is smooth.

Add the cooked tortellini and sautéed beef and vegetables to the sauce. Toss to combine and heat through for an additional 2-3 minutes. Serve hot.