In a small bowl, make the mustard citrus maple dressing. Add and mix all of the dressing ingredients together until the dressing has thickened.
Place the chicken in a frying pan and add 3 Tbs of the dressing on top. Cook over medium heat until the chicken is grilled on both sides. This took me 4 minutes on one side and then 4 minutes on the other side. Then 2 mins on one side and 2 minutes on the other side. Slice the grilled chicken into thin slices.
Add the shredded Brussels sprouts, kale, and cabbage to a large bowl. Top with the sliced avocado, cucumber, apples, almonds, and dressing and toss. (Note: you don't have to use all the dressing, use as much as you'd like). Top with sliced chicken and toss again.