Boil a large pot of salted water for the pasta. Cook it al dente according to package directions. Then about 10 minutes before the pasta is ready, start the sauce.
Lightly season the salmon with Creole Seasoning, salt, and pepper.
Add the oil and butter to a skillet over medium-high heat—cook the salmon for 2 minutes per side.
Take the fish out of the pan and set it aside. Reduce the stove's heat to medium.
Add the sun-dried tomatoes, garlic, and Dijon mustard to the pan. Cook for 30 seconds, stirring constantly.
Add the cream, chicken stock, lemon juice, Cajun seasoning, and salt to the pan. Stir until the sauce is smooth.
Drain pasta and toss it in with the sauce, together with the spinach. Let it cook for about a minute to soak up the sauce. Add more stock if too thick.
Then add salmon, break it up (if desired) or leave it as is. Adjust seasonings to taste.
Remove from the heat. Serve with freshly grated parmesan cheese.