A vin de liqueur (French) or mistela (Spanish) is a sweet fortified style of French wine and Spanish wine that is fortified with brandy to unfermented grape must.
The term vin de liqueur is also used by the European Union to refer to all fortified wines.
These wines are similar to vins doux naturels but are sweeter and have more flavor influence from the added brandy.
The unfermented grape must is fortified with brandy until the solution reaches an alcohol level of 16%–22%.
[1] Vins de liqueur are available in many regional styles and varieties of grape.