Kat Can Cook

0 Trim, core, and shred the cabbage using a mandoline or very sharp knife.  The thinner the shreds, the easier it will be to pull moisture out which we will be doing.  Reserve the outer leaves for fermenting.
1 If using a large fermentation crock, add shredded cabbage to crock, sprinkling in the measured salt and optional spices as you go. If using a Mason jar, put shredded cabbage in a large mixing bowl and sprinkle with measured salt and optional spices. Mix well, then knead and squeeze cabbage for a few minutes to begin to release its liquid.
2 Covering cabbage with the lid between squeezes, continue to squeeze and knead cabbage roughly every 15 minutes for up to 4 hours, until lots of brine has formed and it covers the cabbage when it’s pressed down. 
3 Lay reserved cabbage leaves on top of cabbage and press down until brine rises 1/2 to 1 inch above cabbage. Add stone or glass weights and push down to compress even more. If you still don’t have enough brine, I've added instructions below to help you make more. 
4 Seal fermentation Crock or Mason Jar with airlock lid following manufacturer's instructions. Put in a cool, dark place; 65 to 70°F is ideal. 
9 After a day or two (or three), the fermentation process should kick off more actively and the cabbage should be bubbling away. If the Crock/Mason Jar is quite full, put a rimmed baking tray under it to catch any overflowing liquid.
5 After the first week, feel free to open the vessel, push cabbage back down below brine level - it's very important that the cabbage remains submerged in liquid.  Taste the cabbage to see how it’s going.
6 The sauerkraut is ready when, well, it tastes like sauerkraut!  I usually refrigerate mine at 2-3 weeks. If a tiny bit of mold has formed, it’s usually okay, you can scoop it out and discard.  Refrigerate in a sealed container for up to 6 months.
Make Additional Brine:
7 Dissolve 2 grams of salt in 100 grams of water; 1 cup of water would require about 1 heaping teaspoon of Diamond Crystal kosher salt.