They are created by SpongeBob SquarePants and are basically Krabby Patties, but in assorted colors. They were loved by all of Bikini Bottomies until the colored patties turned their skin into an assortment of colors, and even caused one citizen's' tongue to glow in the dark by itself. Everyone hated them afterward, and they have not been seen since.
The venue in which Pretty Patties were sold was a stand created by SpongeBob and Patrick. There was a stand to sell the patties, and right next to it was a stand that gave money away to customers. The stand was colored yellow and blue. The stand was later taken over by Mr. Krabs, and the Krusty Krab key was given to SpongeBob. After the episode, the stand no longer existed.
SpongeBob and Patrick were so kind, but not so smart, that they just gave the money they earn to an orphanage, criminals from jail, and everyday people. It's unknown if SpongeBob and Patrick gave it to the customers again to get free food and get their money back or more, maybe that's attracting them or the food, no one knows the thing that made everyone have new colors, including that glow in the dark, possibly painted.
When Harold took out a purple Pretty Patty, it was blue from the sighting at the Krusty Krab. In the early showings of "Patty Hype," the Pretty Patty was fully blue.
When the man with the glow in the dark tongue turned out the light, no one knows where the light switch came from.
The last Pretty Patties customer was the man with the glow-in-the-dark tongue.
SpongeBob might have been hinting that he painted the Pretty Patties with edible paint, because when he first introduced them, the patties were displayed on a paint palette.
If Pretty Patties utilized the same recipe for Krabby Patties, SpongeBob would owe Mr. Krabs royalties.
Pretty Patties strikingly resemble macaroons.
For a limited time in June2015, Burger King released a fully red colored burger, mirroring the red patty, although they were not based off Pretty Patties.
When SpongeBob revealed the Pretty Patties to Squidward and Mr. Krabs, he says, "Available in 6 designer colors." However, they are seen in approximately 22 different colors. It is possible that he added the colors as they got more popular.