Start by bringing a large pot of salted water to a rolling boil over high heat. Once boiling, add the linguine or fettuccine pasta and cook according to package instructions until al dente, usually about 8-10 minutes. Drain the pasta in a colander, reserving a splash of the pasta water for later use, and set aside as you prepare the flavorful Cajun sauce.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the diced onion, red bell pepper, and green bell pepper, and sauté for about 5 minutes, stirring frequently, until the vegetables are softened and the onion becomes translucent.

Next, stir in the minced garlic and sliced andouille sausage, allowing them to cook for 3-4 minutes until the sausage is browned and fragrant.

Now, it's time to incorporate the shrimp into the skillet. Toss in the peeled and deveined shrimp and cook for another 3-4 minutes, until they turn pink and opaque.

Pour in a can of diced tomatoes along with the heavy cream, stirring to mix everything together. Season with Cajun seasoning, salt, and pepper to taste. Let this mixture simmer for 5-7 minutes over medium heat until slightly thickened.

Carefully add the cooked pasta to the skillet, tossing it in the sauce for an additional 2-3 minutes. If the sauce is too thick, add a splash of the reserved pasta water.

Remove the skillet from the heat and stir in the chopped parsley and grated Parmesan cheese. Serve immediately.