Geoffrey Zakarian is an Iron Chef and one of the stars of “The Kitchen” on Food Network, my favorite way to start a Saturday morning. In fact, with GZ’s appearance (and he was totally fine with me calling him GZ), I’ve now interviewed 4/5 of the panel with Jeff Mauro being the only holdout. [Jeff! Come do our show!] GZ called in with some expert grilling tips just in time for the unofficial kickoff of barbecue season this Memorial Day Weekend.