Gianduia

Gianduja or gianduia is a homogeneous blend of chocolate with 30% hazelnut paste, invented in Turin during Napoleon's regency (1796–1814). It can be consumed in the form of bars or as a filling for chocolates. Gianduja is chocolate stretched with hazelnut butter. Similarly to standard chocolate, it is made in both plain and milk versions. It may also contain other nuts, such as almond. As a bar, gianduja resembles normal chocolate, except for the fact that it is significantly softer due to the presence of hazelnut oil, which is liquid at room temperature unlike cocoa butter. However, like conventional chocolate, gianduja is usually tempered. Chocolate hazelnut spreads are also notably inspired from gianduja. They tend to use, however, other ingredients, typically cocoa powder and vegetable oils rather than cocoa butter-based chocolate.

Source: Wikipedia