Heat olive oil in a large pot over medium heat. Add diced chicken seasoned with Cajun seasoning, salt, and pepper. Cook until browned and thoroughly cooked, about 5–7 minutes, then set aside.

In the same pot, add more olive oil if necessary. Sauté diced onion and minced garlic until translucent and fragrant, about 2-3 minutes. Add diced bell pepper if using, and cook for an additional 2 minutes.

Stir in orzo pasta, ensuring it's coated with the mixture. Pour in chicken broth and heavy cream, stirring well. Bring to a boil, then reduce to a simmer, covering the pot.

Cook orzo uncovered for 10–12 minutes, stirring occasionally, until tender. If too thick, add broth or cream as needed.

Add the cooked chicken back to the pot along with Parmesan cheese. Stir until well combined and creamy. Adjust seasoning to taste.

Remove from heat, let it sit for a couple of minutes, then serve garnished with fresh parsley.