Take your cabbage and peel back the outer leaves. Save one clean, large leaf for later.
Thinly slice the cabbage into strips, cutting around the dense inner core, which can be discarded.
Place the sliced cabbage in a bowl, add salt, and begin working it with your hands to incorporate the salt. After a minute, begin squeezing the cabbage to extract the water until the cabbage becomes limp.
Stuff the cabbage into a clean glass jar and top with the remaining water at the bottom of the bowl.
Take the cabbage leaf that was set aside, cut into a circle a little larger than the circumference of the jar, and place it inside to ensure that all of the cabbage pieces are submerged under the water to prevent molding.
Let sit undisturbed for 4-5 days and up to two weeks on the countertop until it reaches desired taste. The shorter the time period, the saltier the sauerkraut will be, and the longer it ferments, the tangier it will be. Ferment to your liking by taking a clean fork to taste test, trying to disturb the ferment as little as possible.
Once the desired taste is achieved, keep in the refrigerator for up to six months.