Add chicken broth and heavy cream, bring to a simmer, then stir in Parmesan cheese until melted and smooth.
Cook pasta according to package instructions, reserving pasta water. Toss pasta into the sauce, adding reserved water to loosen if needed. Mix in cooked chicken and parsley.
Garnish with additional parsley and serve hot.
Notes
For a milder flavor, reduce Cajun seasoning. Use fresh Parmesan for best taste.