Trockenbeerenauslese is an extrmely rich, extremely sweet German wine. Generally this is made from Riesling, but it could be made from other varieties such as Sylvaner or Scheurebe.
The word literally means "selected dry berry harvest"; it is a wine made from overripe grapes that have been slightly shriveled, due to being affected by a rot called botrytis.
Producion of a trockenbeerenauslese is extremely limited and time consuming as it takes months for the berries to ferment. These are very sweet, lush dessert wines that are made in tiny quantites are are extremely expensive; they are almost always put in half bottles. The can age for fifty or more years, due to the high sugar content of the wines.
Although the category is most famous in Germany, it is also a legal term in Austria.