If you were worried that Mémé’s closing might have David Katz in a bit of a funk, you can put your fears to rest. He was in fine form when Grub caught up with him at last night’s guest chef happy hour at Morgan’s Pier, where he was hosting Top Chef champ Kevin Sbraga. While the two chefs manned an enormous charcoal grill, cooking up such Brazilian churrasco specialties as Cachaca-marinated skirt steak and grilled chourico, Katz was his jovial self, sipping a can of Sly Fox, cracking jokes and yukking it up with the hungry crowds who tuned out for the casual, open-air collaboration. Though he didn’t divulge what he might be working on next, he told us that he was making the most of his time off, taking his kids fishing, and enjoying what’s left of the summer. On September 10, he will host another guest chef affair with Michael Solomonov.