Planet Foodcourtia

Foodcourtia is a planet taken over by the Irken Empire and converted into one big food court. Alien species from all over the universe come to snack at the fast food restaurants. Every year, the snacking gets so intense that the Foodening begins. During the Foodening, the gravity increases so that no one can leave, and a time warp causes it to last 20 years while less than a year passes outside of Foodcourtia.
After Zim messed up Operation Impending Doom I, he was banished to Foodcourtia, destined to fry things forever under the Frylord Sizz-Lorr in the restaurant Shloogorgh's. But he quit when he found out about the Great Assigning of Operation Impending Doom II. Sizz-Lorr tracked Zim down after waiting through the Foodening and brought Zim back soon before another Foodening was to begin. Zim was able to escape by hiding in some mooshminky that Eric the blob ordered and then stealing a Snacky Cab.
http://www.thescarymonkeyshow.com/features/updates.htm
This information for this planet and the planets below are from the link above.