Bring a large pot of salted water to a boil. Add pasta and cook according to package instructions until al dente, about 8-10 minutes. Drain and keep warm.

Heat olive oil in a large skillet over medium heat. Add onion and bell peppers; sauté for about 5 minutes until softened.

Stir in minced garlic and sliced sausage. Cook for 3-4 minutes until sausage is browned.

Incorporate shrimp into the skillet and cook until pink and opaque, about 3-4 minutes.

Add diced tomatoes and heavy cream. Stir and season with Cajun seasoning, salt, and pepper. Simmer for 5-7 minutes.

Add the drained pasta, tossing for 2-3 minutes to coat evenly with sauce.

Remove from heat and stir in parsley and Parmesan cheese. Serve immediately.