In celebration of Greta Gerwig's highly anticipated Barbie movie, HGTV decided to bring Mattel's Barbie Dreamhouse to life with help from some of the network's biggest stars. Barbie Dreamhouse Challenge (which hits HGTV July 16 at 8|7c) features 15 HGTV designers and one celebrated Food Network chef — and, in true HGTV fashion, the project took on a competitive edge.