Use a grater or a sharp knife to thinly slice the veggies. I used a microplane to grate the ginger.
Weigh the cabbage and beet in grams and multiply by 0.2. Measure out that amount of salt and add it to the mix, along with the coriander seeds.
Use your hands to gently massage the salt into the cabbage and beet mixture.
Let it sit out for an hour, stirring a couple of times, until the veggies release a lot of liquid.
Transfer to a clean airtight jar and allow it to ferment at room temperature for at least 5 days before you refrigerate.
Notes
The key to getting the perfect beet Sauerkraut is to have the perfect concentration of salt. Make sure you use a weighing scale to weigh the amount of salt correctly.
Ensure all the veggies are fully submerged in the liquid. This will keep them from spoiling. This is true for almost all pickle recipes, including pickled radish and pickled cauliflower too.
Avoid placing the jar of Sauerkraut in direct sunlight. It is best to leave it in a cool, dark place at room temperature to get it to ferment nicely.
While it is fermenting, open the jar once every day to allow the built-up carbon dioxide to release.