The pajeon (파전) is often referred to as the Korean pancake, and in many ways it's a good analogy.
Both are made with eggs and flour, but that's where the similarities end.
Pajeons are also made with rice flour and stuffed with all sorts of goodies. 파 (Pa) is the Korean word for onion, the main stuffing in this treat. Rather than use white or yellow onions, the stuffing of choice happens to be green onions. From there, the chef can be creative when adding other ingredients, including octopus, squid, and even kimchi.
It's easy to find street vendors in most town making this treat, but the best place to eat pajeons is when you're coming off a mountain. Most restaurants and stands located close to popular mountain trails will have them as part of their standard menu.
Since pajeons are about 30cm in diameter, they're made to be shared and can run anywhere between W8,000 to W15,000 per pajeon.