A sarcastic counter-expression used when someone has claimed that a person is "layered" – in the sense that while they might be bitter or sour on the outside, on the inside they're actually sweet. The expression refers to the idea that as with the pastry in question, while the top seems crusty and mean – and there might be some sweetness underneath – at the TRUE core of the person, they really ARE just crusty and mean. So the expression refers to someone who is truly rotten to the core, and that the sugar they throw out is merely a ploy to try to keep people from realizing this. Charismatic serial killers, or brutal tyrants, for example, are layered like pie.
The observation leading to this phrase was first made by the character of Dr. Horrible/Billy (Neil Patrick Harris) in "Dr. Horrible's Sing-Along Blog" in reference to Captain Hammer (Nathan Fillion), as shown below.
Penny: At first I thought he was kind of cheesy–
Billy: Trust your instincts.
Penny: But, he turned out to be totally sweet. Sometimes people are layered like that. There's something totally different underneath than what's on the surface.
Billy: And sometimes there's a third, even deeper level, and that one is the same as the top surface one.
Penny: Huh?
Billy: Like with pie.

Woman with black eye: I know my new boyfriend might seem like a drunken, misogynistic ball of domestic violence waiting to happen, but he's actually really nice, he's layered like that. And now he's promised to only beat me on Wednesdays!
Friend: Yeah, layered like pie. Call the cops on him!
by Astrolounge January 17, 2010
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