Like the cupcake before it, the macaron, a French confection that resembles a pastel-colored sandwich cookie, is ready for its close-up.

It has been featured on film and television, in magazine articles and a new book called "I Love Macarons" by a Japanese pastry chef. Once the preserve of high-end French patisseries such as Ladurée and Pierre Hermé, macarons are showing up at retailers like Whole Foods, Trader Joe's and Starbucks. Even McDonald's is selling a scaled-down version in its McCafés in France, backed by ads showing...