Cook the risoni (or orzo) pasta according to package directions and drain. Meanwhile, microwave the cauliflower rice according to package directions. Mix together the cooked risoni and cauliflower rice, cover and set aside.
Meanwhile in a large, non-stick frying pan, melt the butter over medium heat.
Add the chopped carrot and celery and sauté for a few minutes.
Season with parsley, salt and pepper. Add the chicken broth. Bring to a simmer. Cover and allow to simmer until the carrot and celery are very tender, approximately 10 minutes.
Uncover and stir in the cooked risoni, cauliflower rice, rotisserie chicken and half and half. Cook, stirring often until the mixture is starting to thicken.
Taste and season with more salt and parsley if necessary. Serve.