A Burger-like food, made from freshly picked tomatos, sea weed lettuce, cheese and pickles under 2 steamy, soft buns, sold only at the Krusty Krab. It is very unique as the secret of it's unbeatable taste is a very well hidden secret formula, which is never mentioned in the entire series (although in Plankton's Army a fake forumula was introduced to fool and scare Plankton who, up to this date, tries his hardest to steal the formula).
Not even his daughter Pearl knows the formula, but although it's secretive, Mr. Krabs and SpongeBob (since he's the frycook) aren't the only one who knows the secret, Squidward Tentacles found the recipe in the most unexpected location: under the mattress of Mr. Krabs' bed at home.
It is unknown if the secret will ever reach the public, but in the real world, a food store somewhere sells a burger called the "Krabby Patty" except for the name, it has no relevance to it's underwater cartoon counter-part.
The Krabby Patty can also be made into Krabby Patty Pizza which is delivered once by Squidward Tentacles. This idea never saw the light of day after that delivery.
 How to Make A Krabby PattyFirst comes the bun, then the patty, followed by ketchup, mustard, pickles onion, lettuce, cheese, tomatoes and bun- in that order.
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