Chop the cabbage and transfer it to a large bowl. Sprinkle with salt. Massage the salt into the cabbage using your hands until well incorporated. Cover the bowl and let sit for 30min until wilted and water has been released.
Discard water and allow it to drain in a colander for a couple of minutes.
Combine sauce ingredients in a food processor and process until well combined.
Add 2-3 Tbsp of the chili paste to the cabbage and toss with your hands, using gloves, until evenly combined and the cabbage is thoroughly coated with the mixture.
Once combined, place the mixture in a jar pressing down and packing tightly so that the mixture is submerged in its own liquid. Cover the jar, place over a plate and let sit in a cool, dark place for 24 hours (the mixture may bubble). Each day of fermentation, remove the lid to release gases and press down on the mixture to keep it submerged. Depending on the temperature the fermentation can take slower or quicker. So, taste a sample each day to decide if the level of fermentation is to your liking. Refrigerate for up to 1 month.
Use the sauce to ferment cucumber and other vegetables.