Cut the chicken into bite-size pieces and set aside. Chop the carrots, onion, and garlic, then measure the rice and broth.
Heat butter and olive oil in a large pot over medium heat until melted and glossy.
Add the onion and carrots, then sauté for 4–5 minutes until softened.
Add the chicken, salt, and black pepper. Stir and cook until the chicken turns opaque.
Stir in the rice, then pour in the chicken broth or stock. Mix once to prevent sticking.
Bring to a gentle simmer, cover, and cook for 15–18 minutes until the rice is tender and creamy.
Remove from heat and let rest for 5 minutes.
Stir in Parmesan cheese and parsley if using. Serve warm.