Cassis as a flavor is sweet and fruity, like the taste of black currants or blackberries. Creme de cassis is a liqueur made from black currants.
In the wine-tasting world, when a wine has hints of cassis, it means that the wine tastes a little bit fruity. The flavor is a mix between that of a dark berry and the pomegranate. It may finish with slightly bitter notes from the pips of the berry used in the drink. The aroma may be very sweet and pungent like a berry jam or marmalade.
The liqueur, creme de cassis, is the beverage that influenced the use of cassis as a flavor. It has a deep purple or red color and an alcohol content of about 16 percent. The liqueur is usually served with champagne or sparkling wine. The more adventurous can try reducing the liqueur into a syrup and serving it over ice cream.
Modern cassis first appeared in 1841, but it evolved from a fortified-fruit wine called ratafia de cassis. This fortified alcoholic drink had been in production for centuries prior. It may have its origins in the 16th century as a drink used by French monks. While not as popular in the United States, cassis is widely distributed in France.