Cook the pasta according to package directions.
While the pasta cooks, make the white sauce.
Melt the 4 tbsps. of butter in a pan. Add the flour, all at once, stirring to break up lumps. Cook the mixture over medium heat for three to five minutes or until lightly browned around the edges. Pour in the milk, little by little, stirring all the time. Use the minimum amount first; if the sauce is too thick for you, add the rest of the milk. When all the milk is in, turn off the heat. Stir in the cheese until melted. Taste, add salt and pepper as needed.
Drain the pasta and add to the sauce. Toss. Set aside and keep warm.
Cut the salmon into thin slices, about 1/4 inch. Arrange slightly overlapping one another (this is for fast cooking). Sprinkle with salt and pepper.
Heat the 2 tbsps. of butter in a frying pan. Using a wide spatula, scoop out the salmon slices in one go and lay on the hot butter. Cook for two minutes over high heat, carefully flip over and cook for another minute.
Spread the pasta with white sauce on a platter. Arrange the salmon on top.
Place the cream cheese in a microwavable bowl. Add about 4 tbsps. of milk. Microwave on HIGH for about a minute to soften. Stir. Add snipped parsley, and salt and pepper to taste (chili flakes are great too).
Pour the cream cheese mixture over the salmon. Sprinkle snipped parsley over everything. Serve.