Spaghetti is an Italian food that first appears in the episode "Imitation Krabs."
Spaghetti is a long, thin, cylindrical, solid, light yellow pasta. It is a staple food of traditional Italian cuisine. Like other pasta, spaghetti is made of milled wheat and water, and can also contain tomato sauce. A famous side dish to them is meatballs.
Italian spaghetti is made from durum wheat semolina, but elsewhere it may be made with other kinds of flour.
After the Picnic Supply Inc. plane drops its load of food to avoid crashing, a table of said food lands in the middle of Kelp Forest, proving Squidward's metaphor about all SpongeBob and Patrick's problems falling out of the sky to be literal. Squidward wants something to eat and asks the Magic Conch Shell if he should try the spaghetti or the turkey, to which it replies "Neither" because the shell hates Squidward.
Spaghetti is eaten during Cashina and Mr. Krabs' date at Fancy! As Plankton struggles to pull another noodle in through Cashina's mouth hole, Krabs slurps on the same noodle at the same time. The noodle gets tighter and tighter as he slurps more and more of it, to the point where Plankton can be seen almost falling out of Cashina's mouth for a second.
He just manages to pull himself back in before Mr. Krabs sees him. The noodle bridging Cashina and Mr. Krabs' mouths gets so short, Krabs has to lean over the table and Cashina has to stand on top of the plate of spaghetti. Becoming desperate, Plankton pulls out a pair of scissors and cuts the noodle, sending both Cashina and Mr. Krabs flying in opposite directions.
SpongeBob walks into his living room and realizes that it is a mess, but has no recollection whatsoever of making one. Out of nowhere, spaghetti falls on him and he is left confused since he does not remember eating spaghetti either. He opens a door on his stomach to confirm this and is proven right by a Krabby Patty, French fries, and a soda sitting there instead. He stores the spaghetti in his stomach. SpongeBob then realizes that Patrick's sleepwalking is what caused the spaghetti to land on him, among the other mess made.
While saving Bubble Bass' lost action figure, Patrick and Bubble Bass notice that they are in a trap by Hoodoo Guru. While Bubble Bass cannot break out of the trap, Patrick asks him if he wants a plate of spaghetti and then it actually turns out that they got trapped in it.