How Magnolia Bakery tweaked its banana pudding recipe so it can be frozen and delivered anywhere

While Magnolia’s cupcakes might get the cameos on sitcoms, true fans of the New York–based bakery know that its banana pudding is its ace dessert. After all, the creamy, fluffy confection made with layers of whipped cream, fresh bananas, vanilla pudding, and wafer cookies is its bestseller, with over 2.3 million cups sold last year.  The bakery, which opened in 1996, put what had been a regional Southern dessert on the radar of sweets lovers around the world. Now Magnolia is bringing...