What is a good comedic poem that runs three to five minutes long when read aloud?
"Bèrenger of the Long Arse" by Guèrin is a good example of a fabliaux, which is a long-format comedic poem from 13th- and 14th-century France. It is about a woman who proves her knightly husband to be a coward by dressing up as a man, defeating him in combat and forcing him to perform obscene sexual favors for what he presumes to be another man.
Fabliaux shock and delight modern audiences with their degree of lechery, scorn, schadenfreude and general irreverence, especially because most audiences assume everything "medieval" to be buttoned-up and boring. Fabliaux are down, dirty, scurrilous, scatological, obscene and written to entertain a crowd. They have nothing to do with courtly love or church teachings and everything to do with fornication, humiliation, puns, double entendres and slapstick comedy. Most fabliaux will run three to five minutes when read out loud, but some are much longer. Many fabliaux have been translated into modern English and are available free on the web. "The Butcher of Abbeville" by Eustache d'Amiens, "The Tale of the Priest's Bladder" by Jacques de Baisieux, "Gombert and the Two Clerks" by Jean Bodel, and "About a Woman and Her Paramour" by Marie de France are several more examples of fabliaux.