Ganache

Ganache (; from the French word for "jowl") is a glaze, icing, sauce, or filling for pastries  made from chocolate and cream. Ganache is normally made by heating cream, then pouring it over chopped chocolate of any kind. The mixture is stirred or blended until smooth, with liqueurs or extracts added if desired. Butter is traditionally added to give the ganache a shiny appearance and smooth texture.