Cut the green cabbage into quarters, slice away the tough core, and shred it as thinly as you can with a sharp knife or a food processor. Put the shreds in a colander set over a bowl or the sink.

Toss the shredded cabbage with the tablespoon of fine salt and let it sit for 30 minutes. The salt draws water out of the cabbage, and you will see it collecting in the bowl underneath.

Rinse the cabbage under cold running water, then drain it well and spread it on a clean kitchen towel. Pat it dry, or squeeze it in the towel in small handfuls, until the shreds feel barely damp.

Whisk the vegan mayonnaise, apple cider vinegar, Dijon mustard, maple syrup, celery seed, pepper, and the quarter teaspoon of salt in a large bowl until the dressing is smooth.

Add the dried cabbage, grated carrots, red cabbage, and green onions to the bowl. Toss until every shred is coated, then cover and chill for at least 30 minutes before serving.