Oooh, it's good. I make it at home with my little blow torch and everything
Basic creme brulee is an eggy/vanilla custard that's cooked in an elongated ramekin. It generally needs to be cooked in a water bath, i.e., the ramekins are placed in a pan that has a little bit of water. The water doesn't get in the custard (ideally).
The custard is cooked and usually chilled.
Right before you eat it, you sprinkle sugar on it. Different types of sugars will give you different tastes and textures. I like powdered sugar the best, but I've used plain granulated, as well brown. But the cook will sprinkle sugar all over the top, level it off a bit, discard the excess and literally flame the sugar so as to melt and almost lightly burn it. After the sugar's been melted, it will harden, so you'll have this candy "shell" on top of the custard.
It's good stuff.
You can also add flavors to your custard. My favorite is pistachio at Jiko in Disney.