The sweet, yeasted buns and cakes of northern Europe, many of which began as indulgences reserved for holidays, have migrated across borders and to far-flung colonies. American coffee cake, for example, is descended from a raisin-studded holiday cake called kugelhupf that's eaten in Alsace, Austria, and Germany. What we call the danish was allegedly invented by Viennese pastry chefs working in Copenhagen, and pain au chocolat, though widely understood to be French, is also believed to be a Viennese invention. The icing-slathered cinnamon roll is a riff on spiced spiral buns such as Sweden's kanelbulle and England's chelsea bun. And Mexico's pan dulce, a yeast bun that comes in a range of forms, is a legacy of successive periods of occupation in that country by the Spanish and the French.