Heat olive oil in a large deep skillet or Dutch oven over medium-high heat.
Add sliced chicken sausage and cook until browned on all sides, about 5 minutes. Remove sausage from the pan and set aside.
In the same pan, add diced green bell pepper, red bell pepper, and onion. Cook until softened, about 4 minutes.
Add minced garlic and cook for 1 minute until fragrant.
Stir in Cajun seasoning, smoked paprika, and cayenne pepper, coating the vegetables evenly.
Pour in chicken broth and heavy cream, stirring to combine.
Add penne pasta and diced tomatoes to the pan. Stir well to submerge the pasta in the liquid.
Bring the mixture to a boil, then reduce heat to medium-low. Cover and simmer for 15 minutes, stirring occasionally, until pasta is tender and most of the liquid is absorbed.
Return the cooked chicken sausage to the pan and stir to combine.
Sprinkle shredded cheddar cheese over the pasta and cover for 2-3 minutes until the cheese melts.
Season with salt and black pepper to taste.
Remove from heat and garnish with chopped fresh parsley before serving.