Deonjang - fermented soybean paste - is probably the most important ingredient in Korean pantry, it is a base of Korean soy sauce (Ganjang) and Korean Chilli sauce (Gochujang). Similar to Japanese Miso, it is made with cooked/fermented soybeans but unlike to Japanese Miso, Deonjang is fermented much longer period creating more complex flavours and aromas. So obviously, it is a bit stronger in taste than Miso, but very addictive and super healthy. You can make soup or stew with this, or you can also use it as a dip.
There is a good piece of read on Bon Appetit by Christina Chaey: