1. To get the most benefits from the good, healthy bacteria, make sure your environment is clean (cutting board, knife, bowl, the jar you’re going to use and your hands should be washed).
2. Remove the outer leaves, slice cabbage into quarters and remove the core. Then slice cabbage into very thin ribbons. Transfer to a large non-metallic bowl.
3. Sprinkle salt over shredded cabbage. Work the salt into the cabbage by massaging and squeezing the cabbage with your hands for about 5-7 minutes (the most difficult part). The liquid will be running when you squeeze a handful of cabbage, you should have enough liquid to cover the cabbage in the jar (if you don’t have much brine, cover the bowl and allow it to sit for 30-40 minutes).
4. Stuff the cabbage very tightly into the jar, few handfuls at a time, pressing it into the bottom with your hand to remove air pockets (I used my fist). You should have some brine on top of the cabbage once it’s all been pressed (if you still don’t have enough liquid, you can add a little water at this point, just to cover the cabbage). Make sure you leave about 2 inches of free space in your jar.
5. Add some weight (I used a smaller dish that just fit in, you can use a jelly jar), to keep cabbage submerged. Half close the lid, so that some air can still flow in.
6. Ferment for 3-10 days, keeping away from direct sunlight. Check daily and press down if it’s floating above the liquid. Taste test starting at Day 4, until you reach the desired tartness (I transferred mine to the fridge on the 7th day). Remove weight and store in your fridge for up to 6 months.