Preheat the oven to 425°F (220°C) and line a baking sheet with parchment paper if desired.
Rinse and core the cauliflower, then cut it into bite-sized florets.
In a large mixing bowl, combine the olive oil, garlic powder, onion powder, salt, black pepper, and paprika (if using). Whisk until well mixed.
Add the cauliflower florets to the bowl and toss until they are evenly coated with the oil and seasoning mixture.
Spread the coated cauliflower in a single layer on the prepared baking sheet.
Roast in the preheated oven for 20 minutes.
After 20 minutes, remove from the oven and sprinkle the grated Parmesan cheese over the cauliflower. Toss gently to mix.
Return to the oven and roast for an additional 10 minutes, or until the cauliflower is golden brown and crispy.
Remove from the oven and let cool slightly before serving.