Preheat oven to 350 degrees.
In a small container with a lid combine soy sauce, vinegar, sesame oil and honey. Shake to combine. Grate or thinly slice cucumber (excluding center and seeds) and carrots. Combine with liquid and cashews in a small mixing bowl. Cover and refrigerate slaw while preparing salmon.
Place salmon filets skin-side down on baking sheet. Season with a pinch of salt and pepper and brush each filet with hoisin sauce. Bake salmon for 10 minutes (or to nearly to doneness). Turn on broiler and continue to cook until glaze begins to bubble and turn golden, about 4 minutes more.
Toss slaw and serve immediately with salmon.