1. Pull kale leaves away from stems and wash and dry them. Stack the leaves, roll them up, and cut into thin ribbons. Place kale in a large mixing bowl and add a generous sprinkling of salt. Massage salt into kale with your hands for 1 minute. Add kohlrabi, fennel, olive oil, and apple cider vinegar and toss to coat. Add cranberries and walnuts and toss again. Add additional salt, olive oil, or apple cider vinegar to taste. Serve chilled.