Madeira wine gets part of its distinctive flavor from being deliberately heated in warm rooms called estufas — a process discovered after producers noticed wine that survived hot sea voyages tasted better, not worse.
Madeira is a fortified wine produced on the volcanic island of the same name, aged and warmed for months to develop its rich, slightly caramelized character. Styles range from dry to very sweet, often served as an aperitif or with dessert.