In a bowl, toss the sprouts with olive oil, garlic powder, onion powder, Italian seasoning, red pepper flakes (if using), and kosher salt.
Line a baking sheet with parchment paper. Sprinkle an even layer of grated Parmesan cheese on the sheet. Place the seasoned sprouts, cut side down, on the cheese.
Roast for 25-35 minutes or until the undersides are crisp and golden. Serve warm.