Toss cabbage and 1 teaspoon salt in a colander or large mesh strainer set over a medium bowl. Let stand until cabbage wilts, 1 to 4 hours. Rinse cabbage under cold running water (or in large bowl of ice water if serving slaw immediately). Press, but do not squeeze, to drain; pat dry with paper towels. (Cabbage can be stored in a resealable plastic bag and refrigerated overnight.)
Stir together onion, honey, vinegar, oil, mustard, and tarragon in a medium bowl; set dressing aside. Immediately toss cabbage, apple, and fennel in dressing. Season to taste with salt and pepper. Cover, and refrigerate until ready to serve.
After chopping the cabbage, Chris sprinkles it with a teaspoon of salt and lets it sit for a few hours to draw out the excess water. Unsalted cabbage will leech water into the dressing, making the slaw overly wet and separating the dressing from the greens.
The seasonings for this cole slaw make this a novelty. I love the fennel and green apple together. It held up well for a picnic - very light and refreshing.
This coleslaw is just as delicious with dill too, BTW.
This is my go to coleslaw recipe cuz it's got nothing to do with mayonnaise! It's just a great combination of flavors to which I also like to add radishes and grated carrot for extra color and pop of flavor.