Samgeoli Korean Restaurant is nestled in a tiny shopping center on Fullerton’s long stretch of Euclid. The dining room fills up quickly at lunchtime, when customers sit down to an assortment of banchan that’s spicy, fermented and pickled. For layers of umami, order the bossam. Take a piece of the sweet pork belly from the arge, circular, cast-iron plate and place it in the middle of a napa cabbage leaf. Top it with briny raw oyster, daikon kimchi and light smear of doenjang (fermented soybean paste) or a dab saeujeot (salted-fermented tiny shrimp sauce) for a pungent kick. The dish, which can easily feed two or three people, is served with slivers of daikon kimchi, a natural probiotic that will help you break down everything you’ve eaten.