As a little kid, I was always told that a Hamantasch is representative of Haman's three cornered hat. Is there an actual source that says Haman wore a three cornered hat or is it just Folklore?
I was told the following by a Rebbe of mine (My Yiddish is sorely lacking, so can't verify it to be true, but why would he make this up?):
In Europe, they made "hamantaschen" out of poppy, which in Yiddish is Mon. A pocket in Yiddish is a Tasch. Mon-Tasch, or plural Mon-taschen, (poppy pockets) were a popular purim snack. The similarity of Mon to Haman caused people to start calling it that, and afterwards the "explanation" came along.