Why were these “poppy pockets” customarily eaten on Purim?It was in fulfillment of a custom to eat seeds on Purim. 1) records, when Daniel, Hanania, Mishael, and Azaria were forced into service in Nebuchadnezzar’s court, Daniel requested that they be given just seeds and water to eat so they wouldn’t have to defile themselves with non-kosher food.(Based on Ta’amei Ha Minhagim 895.) Finally, the three corners of the hamentaschen might allude to the three-way struggle between Ahasuerus, Haman and Esther or the three Patriarchs in whose merit we were saved (Otzar Dinnim u’Minhagim, based on Midrash, Sefer Matamim Purim 2).For a more complete treatment of this interesting topic see here.There is actually no classic source I am aware of which makes mention of Haman wearing a three-cornered hat. So it’s a perfectly good theory, but it’s really only a speculation.This is one of the suggestions given for the custom to eat the triangularly-shaped hamentaschen (or hamantashen) on Purim – that perhaps Haman wore such a hat and we eat them to commemorate his destruction. (It no doubt stems from the days when people imagined powerful goyim as wearing Napoleon-like three-cornered hats.) The Yiddish word tasch means pouch or pocket.The earliest source I know of which mentions this theory is Otzar Dinnim u’Minhagim (Collection of Laws and Customs, by Rabbi J. Thus, others suggest that the term is a reference to the Haman’s pockets – meaning the vast treasure he offered Ahasuerus for permission to wipe out the Jews (Esther 3:9).(Otzar Dinnim u’Minhagim suggests further that the many poppy seeds inside the “pocket” allude to the myriad coins he offered the king.) In Modern Hebrew hamentaschen are known as “oznei haman” – “Haman ears” – and there exist several early references to such a name for them.
Rather than performing open miracles, God quietly guided the course of events to bring about our salvation.Thus, severed ears are reminiscent of Haman’s fate (I know, this makes them just a bit less appetizing). Hamentaschen were always classically filled with honeyed poppy seeds, mohn in Yiddish.And since tasch is a pocket, the treats might have originally been known as mohntaschen, which due to their association with Purim became known as hamentaschen (Sefer Matamim, Purim 2).(Both explanations appear in the work Menucha u’Kedusha ().) An additional insight is offered based on the fact that Purim is a minor holiday.Unlike the major holidays, we are not restricted from performing labor on Purim.