Combine the cabbage and bell peppers in a large bowl and mix well. Toss with the sugar and allow to macerate for 15 minutes.
For the dressing, combine all the ingredients in a blender and blend until smooth. Add the apples, watercress, shallots, chile pepper, scallions, dill, and parsley to the cabbage and peppers and mix well. Toss with the dressing to coat and serve.
Excerpted from Charred & Scruffed by Adam Perry Lang (Artisan Books). Copyright 2012. Photographs by Simon Wheeler.