01 - Heat olive oil in a large pot or deep skillet over medium-high heat. Season diced chicken with salt and pepper, add to the pot, and cook until golden and cooked through, about 5-6 minutes. Transfer to a plate and set aside.
02 - Add butter to the same pot. Once melted, stir in onion, carrots, and celery. Sauté until softened, approximately 5 minutes.
03 - Sprinkle flour over the vegetables and stir constantly for 1 minute to cook out the raw taste and form a roux.
04 - Gradually whisk in chicken broth to prevent lumps. Bring the mixture to a gentle simmer. Stir in orzo, garlic powder, thyme, and parsley. Reduce heat to medium-low and cook uncovered, stirring occasionally, until pasta is al dente, about 10 minutes.
05 - Return the cooked chicken and frozen peas to the pot. Simmer for 3 minutes to heat everything through.
06 - Pour in heavy cream and add Parmesan cheese. Stir until the sauce is creamy and cheese has melted. Adjust final seasoning with salt and pepper if needed.