Creme de menthe

Crème de menthe (pronounced: [kʁɛm də mɑ̃t], French for "mint cream") is a sweet, mint-flavored alcoholic beverage. Its flavor primarily derives from Corsican mint or dried peppermint. It is available commercially in a colorless version (called "white") and a green version (colored by the mint leaves, or by added coloring if made from extract instead of leaves). Both varieties have similar flavor and are interchangeable in recipes, except where color is important.

Crème de menthe is an ingredient in several cocktails, such as the Grasshopper and the Stinger. It is also served as a digestif and used in cooking as a flavoring (see Mint chocolate). It is also a primary component of the popular South African shooter known as the Springbokkie.

The traditional formula steeps dried peppermint or Corsican mint leaves in grain alcohol for several weeks (creating a naturally green color), followed by filtration and addition of sugar.

...
Wikipedia