Break bread into small pieces into a baking dish, Drizzle melted butter over bread. Sprinkle with raisins if desired.
Combine eggs, milk, sugar, cinamon and vanilla. Beat well. Pour over bread mixture. The mixture must cover the bread. Use a fork to push down the pieces of bread that are exposed to absorb the mixture.
Bake for 45 minutes, or till the top springs back when lightly tapped.