Preheat your air fryer to 375°F (190°C). This will ensure that it's hot and ready when you're ready to roast the cauliflower.
Wash and thoroughly dry the cauliflower head. Cut it into bite-sized florets, ensuring they are of relatively uniform size for even cooking.
In a large mixing bowl, combine the cauliflower florets, olive oil, garlic powder, onion powder, paprika, salt, and black pepper. Toss the cauliflower until it's evenly coated with the seasonings.
Place the seasoned cauliflower florets in the preheated air fryer basket in a single layer, making sure not to overcrowd. You may need to cook in batches if your air fryer has limited space.
Air fry at 375°F (190°C) for 12-15 minutes, shaking the basket or tossing the cauliflower halfway through the cooking time. The cauliflower is ready when it's tender on the inside and has a crispy, golden-brown exterior.
Once roasted to perfection, transfer the cauliflower to a serving dish. Garnish with fresh chopped parsley or grated Parmesan cheese, if desired, for an extra layer of flavor and presentation.
Serve your air fryer roasted cauliflower as a delightful side dish with your favorite main course or enjoy it as a tasty and healthy snack.