Cook pasta in salted water until al dente. Reserve pasta water, then drain.
Heat olive oil in a large skillet over medium-high heat.
Add steak bites in a single layer and sear until browned on all sides. Remove and set aside.
Reduce heat to medium. Add butter and garlic; cook until fragrant.
Pour in heavy cream and simmer gently for 2–3 minutes.
Stir in Parmesan cheese until smooth and creamy.
Add cooked pasta and toss to coat, using pasta water to loosen sauce if needed.
Return steak bites to the pan and gently mix.
Season to taste and serve immediately.