Never Say "Pie"

Never Say "Pie" is the seventh episode of Invader Zim : Doomy Doom Doom, preceded by And Then We Saw Things, and followed by Hands of Doom.

Premise
The main plot is that at one day at Skool a pie, which is the only food not disgusting served there, is available, but turns out to be horrible. It's later found out that the pie had a mind-control device in it.