Gather and measure all ingredients before you begin, so everything is ready when you need it.
Prepare the rice base: Mix glutinous rice flour with water in a saucepan and cook on low heat, stirring constantly until thick and glossy like porridge. Remove from heat and let it cool completely.
Activate malt sweetness: Soak barley malt powder in warm water for several hours, then strain out the solids. Add the liquid to the cooled rice mixture and let it rest for 1 to 2 hours.
Mix the gochujang paste: In a large bowl, combine the rice mixture, gochugaru, fermented soybean powder, and sea salt. Mix thoroughly until a thick, sticky paste forms.
Ferment: Transfer the paste into a clean glass or ceramic jar. Smooth the surface and cover loosely. Store in a cool, dark place for at least 30 days, stirring once a week.