1. Bring a large pot of salted water to a boil. Cook the fettuccine according to package instructions until al dente, usually about 10-12 minutes. Drain, reserving 1/2 cup of pasta water, and set aside.
2. While the pasta cooks, heat the olive oil in a large skillet over medium heat. Add the lobster tails and salmon pieces; sprinkle with half the Cajun seasoning. Cook for 3-4 minutes, turning gently, until the seafood is just cooked through. Remove from skillet and set aside.
3. In the same skillet, melt the butter over medium heat. Add the garlic and sauté for about 1 minute until fragrant but not browned.
4. Pour in the white wine, if using, and let it simmer until reduced by half, about 3 minutes. This step brings a lovely depth to the sauce that reminds me of seaside dinners where every sip tells a story.
5. Slowly stir in the heavy cream and bring to a gentle simmer. Allow the sauce to thicken slightly, stirring often, for about 5 minutes.
6. Add the remaining Cajun seasoning, salt, and pepper to taste. Then stir in the Parmesan cheese gradually, letting it melt smoothly into the sauce.
7. Return the cooked lobster, crab meat, and salmon to the skillet. Toss gently to coat the seafood with the sauce. If the sauce feels too thick, stir in a little reserved pasta water to loosen.
8. Add the drained pasta to the skillet and toss everything together until the noodles are thoroughly coated and glossy.
9. Remove from heat and sprinkle with fresh parsley before serving.

One little nugget from my early kitchen days: never rush the sauce. Patience is key, just like when my mum would coax stews to perfect tenderness. Letting the cream and cheese meld slowly ensures the sauce is silky, not grainy, and the spices bloom fully.