The basic method for making sauerkraut goes like this:
Thinly slice the vegetables, then salt them. Pulverize the veggies by crushing them with your hands to release the juices. Pack them tightly into a jar, submerging the veggies underneath the brine. Cover with something—like fabric—so dust and bugs stay out, but air can still escape. (Gas is generated as part of the fermentation process, so don’t cover it with an airtight lid unless it’s one specifically made for fermenting or you run the risk of the jar exploding due to pressure.) Let it sit in a dark cabinet for at least a week—or longer, depending on how sour you like it—then refrigerate.
For this batch:
Cut the cabbage in half. You’ll only be using half for this recipe, unless you decide to double it. (In that case, you’ll need to double the amount of beets, ginger, and sea salt, and you’ll need another jar set-up.) Very thinly slice the cabbage. I used a mandolin, but I’ve done it plenty of times with a sharp knife. Toss the cabbage into a very large bowl.
To prepare the beets, I scrubbed but didn’t peel them. If you’d like, you can peel them, but it’s just an extra step. I thinly sliced the beets into rounds using a mandolin, then stacked them up, and sliced them into matchsticks. Alternatively, you could shred them in a food processor or with a box grater (but that is SUPER messy because beet juice stains). Place the beets into the bowl with the cabbage.
For the ginger, I grated it down finely using a microplane grater. You could also mince it by hand, just be sure the pieces are very small since biting into chunks of ginger is very spicy. Place the grated ginger in the bowl with the beets and cabbage.
Now, add the salt. With clean hands, start to scrunch the veggies as you mix everything together. You have to get aggressive here because you’re trying to break down the cells in the veggies and (with the help of the salt) draw out the moisture. This takes at least 5 minutes of scrunching and squeezing. (Yay for kitchen fitness!) If there’s not a lot of moisture after that time, add more by making some brine (salt water) with 1 teaspoon salt in 1 cup of water. Some cabbages are just drier than others. C’est la vie!
Pack the veggies into a wide-mouth quart-sized Mason jar. Really push them down. (I use my fist or a spoon.) The veggies should come up to about the shoulder of the jar. If there is not at least an inch of liquid covering the veggies, add some brine to cover.
Now, you have a couple options: use a special lid for fermenting to cap it all off or use a simple DIY cover. For this batch, I used a new prototype lid from Kraut Source. It uses a spring mechanism to hold the veggies down under the brine. However, if you don’t have that, the other method I’ve used successfully is to place a 4-ounce jelly jar INTO the wide-mouth jar to keep the veggies submerged. It works really, really well. Click here to see pictures and video.
Place the jar into a bowl or on a plate in case any liquid bubbles out. If you’re using the jar in jar method, cover with a kitchen towel and place in a cupboard or pantry for at least a week. Check the level of the liquid every couple days. If the level has dropped, add more brine. After a week, remove a bit of kraut with a fork and test the flavor. If it’s not sour enough for your liking, keep fermenting. (I find that it’s good for me around 10-14 days, but everyone is different. Some like to keep it going for weeks!) When it’s done, cover with a metal Mason jar lid and refrigerate. Keeps for a few months. Remember to keep the kraut submerged in brine the whole time, even in the fridge or it’ll mold.