Why go
Look for it when you want to compare the same layered dough used for croissants with a dark-chocolate centre. The pastry’s shape is useful shorthand: rather than a crescent, it is a compact roll whose cut surface reveals both the layers and the chocolate inside.
The full story
Pain au chocolat belongs to the viennoiserie family, the French name for pastries linked to Viennese baking. The dough is yeast-leavened and laminated, giving the finished pastry its thin buttery layers. The style arrived in Paris in the early nineteenth century, when Austrian officer August Zang and aristocrat Ernest Schwarzer opened a Viennese bakery on Rue Richelieu. Croissants and pains au chocolat were initially made from brioche dough, then developed toward the flaky pâte feuilletée associated with them today. The name is not universal across France: chocolatine is used in the south-west. For a visitor, the point is the construction rather than the label: a pain au chocolat uses croissant-like layers to frame one or two bars of dark chocolate.