Bring a pot of salted water to a boil. Cook pasta according to package directions until al dente. Drain and set aside.
Heat olive oil in a large skillet over medium-high heat. Add sausage slices and cook for 4–5 minutes, until browned. Remove and set aside.
Season shrimp with Cajun seasoning. In the same skillet, cook the shrimp for 2–3 minutes per side, or until opaque. Remove and set aside with the sausage.
Add onions, garlic, and red bell pepper to the skillet. Cook for 3–4 minutes until softened and fragrant.
Pour in chicken broth and heavy cream. Stir well and bring to a gentle simmer. Add Parmesan cheese and stir until melted. Season with salt, pepper, and more Cajun seasoning if desired.
Return cooked pasta, sausage, and shrimp to the skillet. Toss until everything is well coated in the creamy sauce.
Garnish with fresh parsley or chopped green onions if desired. Serve hot and enjoy.