Preheat the oven to 375°F (190°C).

If using fresh broccoli, blanch it in boiling water for a few minutes until slightly tender.

Drain and set aside.

If using frozen broccoli, thaw it according to package instructions and drain any excess liquid.

Arrange the broccoli in the bottom of an 8 1/2 x 11 inch casserole dish.

Place the cooked and deboned chicken pieces on top of the broccoli.

In a small mixing bowl, combine the cream of chicken soup, sour cream, and chicken broth.

Stir until well combined.

Pour the soup mixture over the chicken in the casserole dish.

Sprinkle the shredded Cheddar cheese over the top of the casserole.

Sprinkle bread crumbs over the cheese, then dot with butter or margarine.

Bake in the preheated oven for about 30-35 minutes, or until the cheese is melted and bubbly, and the top is golden brown.

Serve hot.