Forget the Cronut and all those cupcakes of various sizes and sweetness; the pastry du jour is the canelé (pronounced “KAH-nuh-lay”). Canelés are small, striated French pastries with a dark caramelized exterior and a surprisingly soft, moist center. They’ve been around for centuries, but Canelé by Céline, a new shop on the Upper East Side, is serving them up in a modern way.

Before 2009, Céline Legros, the shop’s proprietor, had no intention of making pastries her career path. She was a lawyer by trade…