Story about a girl who gains every time she hears a food-related word spoken?

[rubarbstreet]

I'm looking for it. The story involves this girl who has a little brother, whose friend (Damon? Some name like that) casts a spell on her where she is instantly filled with whatever food she hears somebody saying. I remember it involved a scene where she hears somebody yelling "hot dog" repeatedly, causing to be magically stuffed with the things. If anyone knows where it is, much guidance to its location would be greatly appreciated. Thanks.

 

[Phrozen]

 

[rubarbstreet]

 

[Observer]