Flavoring made by extracting the
essence of
vanilla beans usually in
alcohol. In fact,
vanilla extract is usually about 35 percent alcohol. And you can buy it in the
grocery store and don't need to be
21. But you didn't hear that from me.
A good vanilla extract is essential (pardon the pun) for any quality baking. You don't want to bother with the McCormick you can get in the grocery store (although it's better than imitation vanilla)--treat yourself and go to Williams-Sonoma and get their exotic vanilla extract from Madagascar vanilla beans, or I go to my food co-op and buy Frontier Organic Vanilla Extract. Sure it's expensive, but you don't need much, and you will be a better cook without even trying.
And never, ever, EVER use imitation vanilla. It's the devil's work.