There are several exceptions to usual Iron Chef rules.
1) Chefs were allowed to prepare rice before the battle. The challenger used "Koshi-hikari" rice (domestic) in a ration of 80 new to 20 old. While the Iron Chef used California rice in a ration of 50 akita-komachi to 50 koshi-hikari.
2) Chefs are allowed to remake their sushi before serving the tasting panel.