Chef was the school cafeteria's cook. He taught them lessons in life and helped them out. He sang songs about sex to explain to the kids, well just about everything. He was hot with the ladies, and firmly believed in the existence of extraterrestrials (visitors). He coached the school sports teams, and led the hardball team to become World Hardball Champions.
Sadly, Chef was killed after joining the Super Adventure Club in "The Return of Chef."
My favorite Chef episodes include "Proper Condom Use," "Chef Goes Nanners," "The Succubus," "Cartman's Mom is a Dirty Slut," "Cartmans Mom is Still a Dirty Slut" and "Chef's Chocolate Salty Balls."