When Luffy offered Sanji a job as the Straw Hat's cook, he just couldn't refuse. Of course he'd miss Zeff, but he wanted to explore and better his culinary skills. So that's what he did. He was in the kitchen cooking chocolate rice balls for Zoro, at Luffy's request, when you came out of Zoro's room. It had affected you deeply when he was attacked by Mihawk, the world's greatest swordsman, and Sanji could sense your sadness.

"Something wrong?" He asked as he melted the chocolate.