Cook the broccoli according to the package directions. Drain it and arrange in the bottom of a baking pan. Arrange the chicken pieces on top.
Make a white sauce with the butter, flour, chicken broth and cream. When the sauce is quite thick and very smooth, stir in the sherry.
Pour the sauce over the chicken. Sprinkle the top with grated Parmesan cheese.
Bake for approximately 15 minutes in a 400F oven.