Heat 1 tablespoon of oil in a large stainless steel skillet over medium-high. Toss the thinly sliced steak with Italian seasoning, salt, and pepper. Arrange the meat in a single layer and leave undisturbed until the bottom sears and browns, about 2 minutes. Stir and cook another 1–2 minutes until it’s no longer pink. Transfer the cooked steak to a large bowl.

Reduce the heat to medium and return the skillet to the stove. Add the sliced mushrooms and cook, stirring occasionally, until they release their moisture and begin to brown, about 8–10 minutes; season with a pinch of salt. Move the mushrooms to the bowl with the steak.

Wipe the pan if needed and warm the remaining 1 tablespoon of oil over medium. Add the sliced onion and bell peppers, season with salt, and cook while stirring frequently until the vegetables soften, about 8–10 minutes. Stir in the chopped garlic and cook for about 1 minute until fragrant, then combine the vegetables with the steak and mushrooms.

Turn the heat up to medium-high and pour in the beef broth, scraping the bottom of the skillet to loosen any browned bits. Stir in the half-and-half and bring the mixture to a gentle simmer. Add the cavatappi in an even layer, return to a simmer, cover, and cook—stirring occasionally—until the pasta is tender but still has a bit of bite and the sauce has thickened, about 10–12 minutes.

Reduce heat slightly, stir in the shredded provolone until it melts into a creamy sauce, then return the beef and vegetable mixture to the skillet. Toss everything together until the pasta is evenly coated and the steak is heated through. Serve immediately.