Preheat oven to 400°. In a 10-in. ovenproof skillet, saute chicken in 2 tablespoons butter until no longer pink. Add broccoli, onion salt, thyme, rosemary and pepper; heat through. Remove from skillet and keep warm.
In same skillet, toast bread cubes in remaining butter until lightly browned. In a small bowl, combine eggs, milk and soup; pour over bread cubes. Stir in chicken mixture. Sprinkle with cheese.
Bake, uncovered, 15-20 minutes or until a knife inserted in the center comes out clean. Let stand 5 minutes before cutting.