In a large pot, cook the penne pasta according to package instructions until al dente. Drain and set aside.
In a large skillet, heat the olive oil over medium heat. Add the sliced sausage and cook for about 5 minutes, until browned.
Add the diced onion, garlic, and bell pepper to the skillet. Sauté for an additional 3-4 minutes until the vegetables are tender.
Stir in the diced tomatoes (with juice), heavy cream, Cajun seasoning, salt, and black pepper. Bring to a gentle simmer.
Once the sauce is heated through, add the cooked penne pasta to the skillet. Toss to combine, ensuring the pasta is well coated with the sauce.
Remove from heat, and stir in the grated Parmesan cheese until melted and incorporated. Adjust seasoning if needed.
Serve warm, garnished with chopped parsley.