I was baking bread a while back. The recipe calls for preheating a pizza stone and a broiler pan. When it is hot you add water to the boiler pan, it turns to steam and you have a moisture for cooking your bread.
On this particular day I couldn't find the broiler pan so I used a pyrex dish.
I also didn't read that it had to be HOT water you add to the dish, not cold.
Oh well, it ended up being a good lesson in following directions.