Fill a large, deep sauté pan or skillet with water and add kosher salt. Bring the water to a boil over high heat and add the fettuccini pasta. Reduce the heat to medium-high and cook the pasta to al dente according to package instructions. Drain and set the cooked pasta aside.
½ pound (8 ounces) fettuccini pasta, ½ tablespoon kosher salt
Return the skillet to the stovetop and reduce the heat to medium. Add 1 tablespoon each of butter and olive oil to the pan. Season the salmon fillets on all sides with Cajun seasoning and sear over medium heat for 4-5 minutes on each side. Set aside on a plate to rest.
1 tablespoon butter, 1 tablespoon olive oil, 1 pound salmon fillet, 2 tablespoons Cajun seasoning
Melt the remaining 2 tablespoons of butter in the skillet and sauté the onion, red bell pepper, and garlic for 5-7 minutes or until softened. Stir in the remaining Cajun seasoning and the tomato paste. Cook for an additional 1-2 minutes.
2 tablespoons butter, ½ large yellow onion, 1 red bell pepper, 3 cloves garlic, ½ tablespoon Cajun seasoning, 1 tablespoon tomato paste
Whisk in the starchy pasta water and the light cream and allow to simmer for a few minutes. It will begin to thicken slightly. Remove the pan from the heat and stir in the parmesan cheese until it is completely melted.
⅔ cup reserved pasta water, ½ cup light cream, 1 cup parmesan cheese
Toss the cooked fettuccini pasta with the alfredo sauce. You can either plate the pasta with the salmon on top or flake the salmon and fold it into the pasta. Garnish with fresh parsley and lemon juice, if desired.
Fresh parsley and lemon juice