Bring a large pot of salted water to a boil and cook the rotini until al dente. Drain and reserve 1/4 cup of the pasta water.

Heat olive oil in a skillet over high heat. Sear sliced ribeye for 2–3 minutes per side until browned and cooked to your liking. Remove and set aside.

Reduce the heat to medium. Add butter and minced garlic to the skillet. Stir until the garlic is fragrant, about 1 minute.

Pour in the reserved pasta water and stir to combine, creating a silky garlic butter sauce.

Toss in the cooked pasta and mix well until all noodles are coated. Add parmesan and stir until melted.

Return steak to the skillet or place it on top of the noodles. Garnish with chopped parsley and serve hot.