For this week's Quickfire Challenge, the chefs must create adish with an ingredient using only the toughest stains as theirclues. Then, in a high-stakes pizza party, the chefs mustcreate pies that are outside of the box to impress guest judgesMichelin star chef Wylie Dufresne and Top Chef All-Star alumnSpike Mendelsohn, who join Kristen, Tom and Gail at thejudges' table.