Preheat oven to 400 F. Rinse sprouts and cut in half lengthwise. Toss sprouts, salt, pepper and olive oil together in a large bowl to coat evenly. Transfer coated sprouts onto a baking sheet lined with parchment paper in an even layer.  Roast for 30 to 40 minutes until vegetables are tender, turning sprouts with a spoon or spatula after about 15 minutes. On a separate baking dish, spread nuts in a even layer and toast in the same oven for about 2 minutes until slightly browned (watch closely - they burn easily!). Whisk together mustard, vinegar and honey. Remove sprouts from the oven and transfer to a serving bowl or platter. Drizzle with vinaigrette and sprinkle with Feta cheese and toasted nuts.

Serve immediately.