Bring a large pot of salted water to a rolling boil. Add cheese tortellini and cook according to package instructions, typically around 3-5 minutes, until tender and floating to the surface. Carefully drain the tortellini, reserving ½ cup of pasta water for later use. Set the cooked tortellini aside while you prepare the other ingredients.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add sliced onions, red bell pepper, and green bell pepper, sautéing for about 5-7 minutes until the vegetables soften and the onions become translucent. Stir occasionally for even cooking. Once done, remove the veggies from the skillet and set them aside in a bowl.

In the same skillet, increase the heat to medium-high and season thinly sliced flank steak or ribeye with salt, pepper, garlic powder, and onion powder. Sear the steak for 2-3 minutes until browned, ensuring it cooks evenly and doesn't overcrowd the pan. Pour in the Worcestershire sauce, stirring to deglaze the skillet and infuse the steak with flavor.

Return the sautéed vegetables to the skillet with the steak. Gently stir in the reserved tortellini and layer the mixture with slices or shreds of provolone cheese. Cover the skillet with a lid, allowing the cheese to melt into a delicious gooey layer, typically for about 2-3 minutes.

Remove the lid and stir in 2 tablespoons of butter along with the reserved pasta water, mixing until a creamy sauce forms. Adjust the consistency to your liking, adding more water if needed. The sauce should glisten and coat the tortellini and steak beautifully.

Plate the Cheesesteak Tortellini hot, garnishing with chopped parsley, grated Parmesan cheese, and a sprinkle of crushed red pepper flakes for a flavor kick. Serve immediately, perhaps alongside garlic bread or a simple green salad.