Bring a large pot of salted water to a boil and cook the cheese tortellini according to package instructions until al dente. Drain and set aside.
Heat olive oil in a large skillet or Dutch oven over medium-high heat. Add the thinly sliced steak in a single layer and sear until browned, approximately 2-3 minutes. Season with salt and pepper. Remove meat from the skillet and set aside.
In the same skillet, add the sliced onions, bell peppers, and mushrooms. Sauté for 5-7 minutes until the vegetables are softened and slightly caramelized.
Add the minced garlic to the vegetables and cook for 1 minute until fragrant.
Deglaze the pan with beef broth, scraping up any browned bits from the bottom. Stir in the heavy cream and dried oregano.
Bring the sauce to a gentle simmer and cook for 3-4 minutes until slightly thickened.
Reduce heat to low and stir in the shredded provolone cheese until completely melted and smooth.
Return the cooked steak and tortellini to the skillet. Toss thoroughly to coat everything in the cheese sauce. Serve immediately.