Fill a large pot with salted water and bring it to a boil. Add the pasta and cook according to the package instructions until al dente. Drain the pasta and set it aside, reserving a cup of pasta water.

Season the steak on both sides with salt and pepper. Heat a skillet over medium-high heat and add a drizzle of olive oil.

Once the oil is hot, add the steak to the pan. Cook the steak for about 4-5 minutes on each side for medium-rare, or adjust the cooking time depending on your desired doneness. Remove the steak from the pan and let it rest for a few minutes before slicing it into bite-sized pieces.

In the same skillet, add the butter and allow it to melt. Toss in the minced garlic and red pepper flakes. Sauté for about 1-2 minutes until fragrant, being careful not to burn the garlic.

Add the cooked pasta to the skillet along with the sliced steak. Pour in a little reserved pasta water to help the sauce coat the pasta evenly. Stir well to combine all the ingredients.

Add the grated parmesan cheese and mix until everything is well incorporated. If the pasta seems dry, add more reserved pasta water until you reach your desired consistency.

Finally, sprinkle the fresh parsley over the top. Toss once more and serve while hot.