Preheat oven to 450 degrees F. Spray a baking sheet with nonstick cooking spray; set aside.
Cut Brussels sprouts in half lengthwise and place in a large bowl with olive oil; toss to coat.
In a small bowl, combine salt, pepper, garlic powder, onion powder and parmesan cheese. Sprinkle on top and stir until evenly coated. Spread in an even layer on prepared baking sheet.
Bake for 18-20 minutes, or until golden brown and fork tender.