Ebony got a warning that when Ignis is cooking he's not to meddle unless Ignis explicitly asked him. So he's been good and Noct has been saved.

Ignis takes out the first batch of eggs and places them on the plate then cracks new ones, seasoning them as well. He glances at Noct who seems to be getting bored with baking waffles- which, true, isn't good. For the waffles.

So... he starts humming the dreaded song as he fries the eggs. Pointedly not looking at Noct. Thank you, Ebony, for giving him the idea.