Preheat oven to 400ºF (200ºC) with the rack in the middle.
Trim the bottom of the Brussels sprouts, and slice each Brussels sprout in half, top to bottom.
Grease a rimmed baking sheet (you can line it with parchment paper if you like).
Pat the Brussels sprouts dry with paper towels and place them in a large bowl. Add olive oil, Italian seasoning, garlic, Parmesan, salt, and pepper.
Toss gently to coat the Brussels sprouts evenly.
Transfer Brussels sprouts to your prepared baking dish and spread them evenly into one layer.
Bake for about 25 to 30 minutes until golden brown.
Transfer the parmesan roasted Brussels sprouts to a large serving bowl and sprinkle with fresh chopped parsley if you like.