This was pretty tasty, and very easy.
With regards to the chicken: If the recipe intended you to use *cooked* chicken, it would have specifically stated that. I used raw boneless chicken breasts cut up into very small bite-size pieces. I cooked at 400 degrees for 30 minutes uncovered, and the chicken was perfectly white and cooked through all the way, and the stuffing was nicely toasted but not overdone.
Make sure you are cutting the chicken up into very small pieces! Also, it helps to make sure you are using only the amount called for (1.5 lbs) and/or are using a large enough baking dish so the chicken pieces aren't all bunched up together.