When it comes to making creme brulee, many people swear by using a water bath. A water bath helps to evenly cook the custard and prevents the top from browning too quickly. It also helps to prevent the custard from cracking.
If you don't have a water bath, you can still make creme brulee. Just be sure to watch the custard closely and remove it from the oven as soon as it is set. Otherwise, you run the risk of the custard overcooking and becoming rubbery.