Run by Buddhist monks, Sujata puts on what is possibly the world's best salad bar. It includes soups, stews, noodles, a dozen different greens, countless pickled things, a make-your-own bibimbap (rice, egg, meat and veggies with chilli sauce) section and even cake. It's all vegetarian, but even non-veggies will get their fill here: it's all you can eat.
Look for the red building halfway between the Uijae Museum of Korean Art and the Hakdong/Jeungsimsa subway station.