1. Begin by cooking the fettuccine pasta according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of the pasta water.
2. While the pasta cooks, pat the steaks dry with paper towels and season generously with the blackening seasoning on both sides.
3. In a large skillet, heat 1 tablespoon of olive oil and 1 tablespoon of butter over medium-high heat. Once hot, add the seasoned steaks and sear for about 4-5 minutes on each side for medium-rare. Adjust the cooking time according to your desired doneness.
4. Remove the steaks from the skillet and let them rest for at least 5 minutes before slicing thinly against the grain.
5. In the same skillet, add the remaining tablespoon of olive oil and the shrimp. Cook for 2-3 minutes until the shrimp are pink and opaque, seasoning with salt and pepper. Remove and set aside with the steak.
6. In the same skillet, add the minced garlic and sauté for about 30 seconds until fragrant. Pour in the heavy cream and bring to a simmer, scraping any browned bits from the bottom of the skillet.
7. Stir in the grated Parmesan cheese and mix until melted and creamy. If the sauce is too thick, add a little reserved pasta water to reach your desired consistency.
8. Add the cooked fettuccine, sliced steak, and shrimp back into the skillet. Toss everything together until well coated in the sauce.
9. Adjust the seasoning with salt and pepper as needed and remove from heat.
10. Serve immediately, garnished with fresh parsley.