"Fun with Veal" is the fourth episode of Season Six, and the 83rd overall episode of South Park. It aired on March 27, 2002.
Stan is appalled when he realizes the veal he's been eating is, in fact, the meat from little baby calves. He and the boys calf-nap the animals and hide them in Stan's bedroom. A standoff ensues and Cartman goes head-to-head with the authorities' greatest negotiator.
Ms. Choksondik's fourth grade class goes on a field trip to a farm, where they discover that veal is actually baby cows meat. The boys are horrified (except Cartman, who joyously claims that they look so tender and scrumptious), and decide to save the calves from becoming veal. Stan, Kyle, and Butters persuade Cartman to help them rescue the calves and bring them to Stan's house. When they are discovered by their parents, the boys barricade the door until they are promised the calves will be safe.
The situation quickly escalates into a standoff between the boys (who are declared terrorists), and the police. To avoid starving, they eat food smuggled in by Ms. Cartman, which contains beef jerky and fried chicken. While most of the group eagerly eats this food, and Cartman happily feeds some of the jerky to one of the calves ("Dude, that's messed up"), Stan feels so strongly about the cause of saving the calves that he becomes fully vegetarian, and eats only apples. Cartman makes fun of this with a bit of foreshadowing, saying, "if you don't eat meat, you become a pussy." As a result, Stan comes down with a strange illness, and develops sores all over his face. Meanwhile, Cartman outwits an incompetent FBI negotiator, and manages to get their hands on heavy weaponry (including an ICBM), and negotiates for a cattle truck driven by Michael Dorn (in full Worf makeup, and he must address Cartman as "captain") to drive them to the airport so they can escape to Mexico. He also gets the FDA to change the term for veal to "tortured baby cow meat" and almost gets North and South Dakota.
The boys are eventually outmaneuvered by the police, who capture the truck. The boys are ultimately successful, however, since at this point the rancher no longer wants his calves. Since veal is now known as "tortured baby cow meat", there is no longer a market for veal. Stan is now so sick that he must be rushed to the hospital, and is confined to his hospital bed for two weeks. The doctor describes Stan's disease as Vaginitis, a condition which occurs when one stops eating meat, and which causes its victim to break out in vaginas all over his body. "If he had stopped eating meat completely," says the doctor, "he would've turned into one giant pussy" (a joke on what Cartman said earlier in the episode). Although the other boys get grounded (except Cartman), their parents decide to treat them for burgers before heading home, to which they excitedly agree.