Sprinkle half of cheese over bread slices. Next, layer thawed chopped broccoli, onion, ham and tomato over cheese. Top with remaining cheese and bread slices.
In a mixing bowl, combine remaining ingredients; beat well.
Pour egg mixture over layered ingredients in baking dish. Cover and refrigerate at least 3 hours or overnight.
Bake, uncovered, at 350 for 40 to 50 minutes, or until toothpick inserted in center comes out clean.