Bring a large pot of salted water to a boil. Add the fettuccine pasta and cook according to the package instructions until al dente. Drain the pasta and set aside, reserving about 1/4 cup of the pasta water.

In a small bowl, combine 1 tablespoon of Cajun seasoning with a pinch of salt and pepper. Pat the seasoning onto the thinly sliced sirloin steak, ensuring each piece is evenly coated. Repeat the process with the remaining Cajun seasoning and the shrimp.

Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Add the seasoned steak slices in a single layer and sear for 2-3 minutes per side, or until browned and cooked to your desired level of doneness. Remove the steak from the skillet and set it aside on a plate.

In the same skillet, add another 1 tablespoon of olive oil if needed. Add the seasoned shrimp and cook for 2-3 minutes per side, or until pink and opaque. Remove the shrimp from the skillet and place them with the steak.

Lower the heat to medium and add a touch more olive oil if necessary. Add the minced garlic and sauté for about 30 seconds, just until fragrant.

Pour in the heavy cream, stirring constantly to combine. Allow the mixture to simmer gently for 2-3 minutes, then stir in the grated Parmesan cheese until melted and smooth. Season with additional salt and pepper to taste.

Return the cooked steak and shrimp to the skillet, tossing them gently in the sauce to coat evenly. Add the cooked fettuccine to the skillet, tossing everything together until the pasta is well-coated with the sauce. If the sauce seems too thick, add a splash of the reserved pasta water to loosen it.

Transfer the Cajun Surf and Turf Alfredo to serving plates or a large platter. Garnish with chopped fresh parsley and serve immediately while the dish is still warm and aromatic. Enjoy!