Measure and prepare the oatmeal.
Add water to doenjang (soybean paste) and mix well, then bring to a simmer over low heat.
Add the oatmeal to the boiling doenjang broth and stir.
When the oatmeal has softened and thickened, turn off the heat and let it cool.
Transfer the finished oatmeal doenjang rice porridge to a bowl.