Cook the penne pasta according to the package directions until al dente. Drain and set aside.
In a small bowl, toss the diced chicken with the Cajun seasoning.
Heat the olive oil in a large skillet over medium-high heat. Add the seasoned chicken, onions, and peppers. Cook for about 7-8 minutes, or until the chicken is no longer pink.
Stir in the sausage slices and minced garlic, cooking for an additional 2-3 minutes.
Lower the heat to medium-low, then pour in the half-and-half. Stir gently and let the mixture come to a light simmer.
Gradually mix in the Parmesan cheese until it's well combined and melted.
Add the cooked pasta to the skillet, stirring everything together until evenly coated.
Garnish with chopped parsley and additional Parmesan if desired. Enjoy!