Gas stations and five-star cuisine are not typically paired together in the same sentence, but in this fourth episode of Bravo's "Top Chef" the contestants are challenged to create tempting dishes solely from ingredients available in a convenience store. For the individual elimination challenge the chefs must face a group of critics who do not have time to wait -- working mothers. At the end of the challenge, one chef will be sent home. Jefferson Hill of Neiman Marcus' Rotunda is the guest judge.