Step 1: Prepare the Pasta
Bring a large pot of salted water to a rolling boil.
Add the pasta and cook until it reaches an al dente texture, about 8 to 10 minutes.
Drain the pasta, reserving 1/2 cup of the cooking water, and set it aside for later use.
Step 2: Sear the Steak
While the pasta is cooking, heat 1 tablespoon of olive oil in a large skillet over medium-high heat.
Pat the steaks dry with paper towels and season both sides generously with salt and black pepper.
Place the steaks in the hot skillet and sear for 4 to 5 minutes per side for medium-rare, or longer based on your desired level of doneness.
Transfer the steaks to a plate and allow them to rest for 5 minutes before slicing thinly across the grain.
Step 3: Prepare the Sauce
In the same skillet used for the steak, lower the heat to medium and add the remaining tablespoon of olive oil along with the butter.
Add the minced garlic and sauté for 1 to 2 minutes, just until fragrant and golden.
If using, pour in the beef broth and let it simmer for 2 to 3 minutes to deepen the flavor.
Stir in the heavy cream and bring the mixture to a gentle simmer.
Gradually whisk in the Parmesan cheese, allowing the sauce to thicken over 3 to 4 minutes.
Season with red pepper flakes (if desired), and adjust salt and black pepper to taste.
Step 4: Bring It All Together
Add the cooked pasta into the skillet with the creamy sauce, tossing well to coat.
Use the reserved pasta water as needed to loosen and smooth the sauce.
Gently fold in the sliced steak, allowing it to warm through just before serving.
Step 5: Serve and Garnish
Top the dish with a sprinkle of freshly chopped basil or parsley, and finish with extra Parmesan cheese if desired.