Place the cabbage in a large, nonreactive bowl. Add the salt, and toss with your hands, making sure the salt gets evenly distributed. Place a plate on top, and place something heavy on top, like a large can of tomatoes, to press the cabbage. Let stand for 30 minutes to an hour.
Remove the weight and plate. Pour off any liquid that has accumulated in the bowl. Take the cabbage in handfuls and wring any excess moisture from it, then pack it tightly into a sterilized one-quart jar. You should be able to get it into one quart. Liquid will release during the packing process; this is normal. Only pour it off if it's overflowing.
Cover the jar with a clean kitchen towel and let rest at room temperature for three to five days. You'll see some bubbles in the liquid, and the cabbage will take on a slightly sour, but not unpleasant aroma.
Turn the cabbage out into a large, nonreactive bowl. Puree the chili paste, vinegar, chili powder, garlic and ginger. Add to the cabbage, add the scallions, and mix thoroughly. Pack the mixture into another sterilized jar; cover with another clean towel and let rest another three to five days. Will keep, covered and refrigerated, for several weeks.