S12, E7: In a Top Chef Canada first, the Judges – Mark McEwan, David Zilber, Janet Zuccarini and Mijune Pak step out from behind the table to become sous-chefs, for a very special Quickfire Challenge. Then, in a high-stakes Elimination Challenge, the final four must make a critical choice: cook with humble ingredients and have time on their side- or splurge on premium ingredients with the clock working against them.