01 - Boil pasta in a large pot of salted water according to package instructions. Drain well and reserve 1/2 cup of the cooking water.
02 - Season steak slices generously with salt and black pepper. In a large skillet over medium-high heat, heat olive oil and sear the steak pieces until browned and cooked to desired doneness, about 2–3 minutes per side. Remove steak from skillet and set aside.
03 - Lower heat to medium and add butter to the same skillet. Once melted, add minced garlic and sauté for 1–2 minutes until aromatic.
04 - Deglaze the skillet by pouring in beef broth, scraping any browned bits from the bottom. Simmer for 2 minutes.
05 - Add heavy cream and grated parmesan cheese to the skillet. Stir regularly and simmer for 3–4 minutes until the sauce thickens. Stir in crushed red pepper flakes if desired.
06 - Add cooked pasta to the sauce, tossing to coat. If needed, incorporate reserved pasta water to adjust sauce consistency. Return cooked steak to skillet and gently combine.
07 - Serve immediately, topped with chopped fresh parsley and extra grated parmesan if desired.