Wikipedia
Jjim is a Korean cuisine term referring to dishes made by steaming or boiling meat, chicken, fish, or shellfish which have been marinated in a sauce or soup. The cooking technique originally referred to dishes cooked in a siru (시루, earthenware steamer mainly used for making tteok) by steaming. However, the name jjim has now come to imply a finished dish with a steamed appearance. The cooking method for most jjim dishes nowadays has changed to boiling the ingredients in broth and reducing the liquid. Pressure cookers are popular for making jjim as well.
Proteins galbi, beef shank or rump, chicken, fish, or shellfish are usually the main ingredients. The ingredients are marinated in a sauce, then put to a boil with a small amount of water. The liquid is then reduced. Various vegetables and other ingredients are added for enhanced flavor.