Slice the Brussels sprouts in half lengthwise and slice as thinly as possible. Slice the red cabbage in half, remove the core and slice as thinly as possible. (You can use a mandoline if you have one–just be careful!).
In a large bowl, combine the Brussels sprouts and the cabbage with the dried cranberries and toasted pine nuts. In a separate bowl, whisk together the Dijon mustard, honey, and sherry vinegar. Add the olive oil in a steady stream, whisking constantly until combined. Season with salt and pepper.
Pour the vinaigrette over the slaw and toss well to combine. Serve immediately, garnished with Parmesan shavings, if desired.