Chocolate bar components: cocoa solids, cocoa butter, sugar, and milk. The relative presence or absence of these define the subclasses of chocolate bar made of dark chocolate, milk chocolate, and white chocolate. In addition to these main ingredients a chocolate bar may contain flavorings such as vanilla and emulsifiers such as soy lecithin to alter its consistency. While vanilla is the most common flavouring, many other flavours are available, including mint, orange, and coffee. Chocolate bars containing other ingredients feature a wide variety of layerings or mixtures that include nuts, fruit, caramel, nougat, and fondant. A popular example is a Snickers bar,
Aero (chocolate) Strawberry flavour and a new variation of a Caramel Aero. While bars were (and still are) produced with chocolate and a liquid caramel, the new Caramel Bubble Bar consists of a Caramel flavoured white chocolate centre with a milk chocolate coating. Japan has produced a number of unique Aero flavours, among them Vanilla Milkshake, Hot Milk, Green Tea and others. They usually consist of a flavoured, coloured chocolate centre and outer milk chocolate layer. Aero Cocoa (plain, Green Tea and Strawberry flavours) is also sold in Japan. Released in 2006, the Aero Vanilla Yogourt flavour was released only in Canada.