Preheat oven to 375°F (190°C).
Cook pasta according to package directions, drain, and set aside.
Heat olive oil in a large skillet over medium heat. Add chicken and Cajun seasoning, cook until browned and cooked through, about 5–7 minutes. Remove chicken and set aside.
In the same skillet, sauté onion, red bell pepper, and garlic until softened, about 3–4 minutes.
Add cream cheese to the skillet and stir until melted and combined.
Pour in heavy cream and chicken broth, stirring to create a smooth sauce.
Stir in shredded cheddar, Parmesan, paprika, salt, and pepper. Cook until sauce is creamy and cheese is melted.
Return chicken to skillet and add drained pasta, mixing to combine all ingredients.
Transfer mixture to greased 9x13-inch baking dish.
Bake for 20–25 minutes, until top is golden and bubbly.
Garnish with chopped parsley if desired and serve hot.