Soup nazi web site, it's a joke.
The Soup Nazi (a.k.a. Yev Kasem) was a fictional character in the sitcom Seinfeld who was portrayed by Larry Thomas. The Soup Nazi was a stone-faced, immigrant chef, with a thick, Stalin-esque moustache who was well-known throughout the city for his delicious soups. He demanded that all customers in his restaurant follow his meticulous (and seemingly arbitrary) soup-ordering instructions to the letter, lest they be refused service by his insistent avowal, "No soup for you!". Some of the soups that he served were cold cucumber, corn and clam chowders, jambalaya, mulligatawny and crab bisque. He got his comeuppance when Elaine discovered his secret recipes. He made a brief cameo in the Seinfeld series finale.
His character was based on an actual soup vendor named Al Yeganeh, who runs Soup Kitchen International in New York City's midtown area. The store is open only part of the year. In the summer, his customers are greeted with a sign indicating he has gone to "Argentina for the winter."
Yeganeh dislikes the Soup Nazi label, for obvious reasons, but he is renowned both for his excellent soups and for his rude treatment of customers. Cosmo Kramer inspiration Kenny Kramer agrees that Yeganeh's nickname is unfair, and jokingly suggests his nickname be changed to Al, The Soup Rat Bastard.