Heat the olive oil in a large skillet over medium-high heat. Add the sliced sausage and cook for about 5 minutes, turning occasionally, until browned on both sides. Transfer to a plate.

Reduce heat to medium. Add the onion and bell pepper to the pan and cook for 4 minutes, stirring, until softened. Stir in the garlic and Cajun seasoning and cook 30 seconds until fragrant.

Pour in the chicken broth and heavy cream, scraping up any browned bits. Bring to a simmer, then stir in the penne. Cover and cook over medium-low heat for 12 minutes, stirring occasionally, until the pasta is tender and the sauce has thickened.

Remove from heat. Return the sausage to the pan, add the Parmesan, and toss until everything is coated and the cheese has melted. Season with salt and pepper to taste. Serve immediately.