Washington

IN A cramped Manhattan apartment kitchen, Chelsey White painstakingly bakes, assembles, frosts and decorates an elaborate mermaid-themed cake. The entire four-hour process is videotaped, then edited down to a few brisk minutes and shared on social media. Its purpose served, the three-tiered, picture-perfect cake is chopped up and jammed into a Tupperware container. Ms White brings all her leftovers to the office. She hates wasting cake.

With over a quarter-million followers and videos that regularly generate hundreds of thousands of views, Ms White is an Instagram celebrity. She used to sell cakes to her fans, but now she makes money selling the concept of cake, in conjunction with such partners as the Food Network and AwesomenessTV.