For the Salad:
- 1 small head red cabbage (about 1 3/4 pounds)
- 1 bunch medium carrots, peeled (about 5)
- 2 tablespoons kosher salt
- 2 Granny Smith apples
- 6 scallions (white and green parts), sliced
- 1 bunch watercress
For the Dressing:
- 3 tablespoons cider vinegar
- 3 tablespoons honey
- 2 tablespoons Dijon mustard
- 1 tablespoon celery seeds or 2 teaspoons caraway seeds
- 1 1/2 teaspoons kosher salt
- Freshly ground black pepper
- 1/3 cup extra-virgin olive oil
For the salad: Quarter and core the cabbage. Set up a food processor with the slicing blade. Slice the cabbage and then transfer it to a colander. Switch to the grating blade and shred the carrots; add to cabbage. Toss the cabbage and carrots with the salt and set colander in the sink until the vegetables wilt, 1 to 4 hours. Rinse cabbage mixture thoroughly in cold water and spin it dry in a salad spinner.
Meanwhile, make the dressing: Whisk the vinegar with the honey, mustard, celery seeds, salt, and black pepper to taste in a small bowl. Gradually whisk in the olive oil, starting with a few drops and then adding the rest in a steady stream to make a smooth, slightly thick dressing.
Quarter, core, and shred the apples. Toss the cabbage mixture with the apples, scallions, and about 1/2 cup of the dressing. Refrigerate until chilled and the flavors come together, about 1 hour. When ready to serve, toss the watercress with the remaining dressing. Make a ring on a platter with the watercress, and mound the coleslaw in the middle of the ring.
Know-How: Salting the cabbage gives the slaw its characteristic tender bite, as well as expressing excess liquid. If you skip this step, your salad will be soggy and bland.