Self-important smirking wasn't the same as a smile or a laugh, but at least he seemed amused? Hell, if she knew. "You eat more of that, and you're likely to self-destruct and be perpetually grumpy." She said back. Seriously, she wasn't all that particular about what she or other people ate, but she knew this meal was pure crap.
Tastey but crap.
"... from the self-destructing." She was only just realizing that he wouldn't be able to look grump if he did self-destruct. "Shut up," she said before he could say a thing. "You know what I mean."