Prepare the dressing by mixing together the mustard, maple syrup, apple cider vinegar and salt together in a small bowl. While whisking, drizzle in the olive oil until a creamy dressing forms.
In a large bowl, toss together the shredded Brussels sprouts and chopped kale. Drizzle with the teaspoon of olive oil and add the pinch of salt.
Using your hands, massage the kale and Brussels sprouts for about 3 minutes or until tender.
Add the onion, bacon, cranberries and pumpkin seeds.
Toss with the dressing and serve!