The Purim Seuda often contains the specialty dish traditionally associated with the holiday, the Kreplach, triangular shaped wontons, eaten as a separate dish or served in soup, reminding us of Haman's tri-cornered hat.  Kreplach are customarily served in holiday meals whenever a "beating" takes place: Thus, it is traditional to include Kreplach during three specific festive meals each year.  Before Yom Kippur, as it once was common for men have themselves flogged, on Hoshanah Rabbah when the we beat willow branches, and on Purim when Haman is beaten.

In addition to the Kreplach, some serve longer than usual braided Challah,  known as keylitsh or kulich (Russian).  The braid on the challah are a reminder of the long rope on which Haman was hanged. 

Some folks include a Turkey dish ("Hodu" in Hebrew), commemorating Ahsuerus's reign from India ("Hodu") to Ethiopia; the turkey is also symbolic of the king's foolishness. 

Desert, of course, is highlighted by the Hamentashen (Yiddish for Haman's pockets), the three cornered filled cookie.  In Israel, the hamantashen are referred to as "Oznei Haman" - the ears of Haman.