Wash, pat dry and cut the pumpkin in half. Scoop out the flesh and the seeds. You can save the seeds for roasting them later (refer my Air Fryer Pumpkin Seeds recipe).
Then cut the pumpkin into 1 - 1 ½ inch chunks or wedges, without the skin.
Transfer the pumpkin to a bowl. Add olive oil and season with garlic powder, ground cinnamon and salt. Toss them well, so they are all coated with the seasoning.
Preheat the air fryer to 380°F (190°C). Add the seasoned pumpkin to the air fryer basket and spread them in a single layer (cook in batches if required).
Air fryer them at 380°F (190°C) for 10-15 minutes or until golden brown and crisp. shaking the basket halfway through.
Roasted pumpkin is ready. Remove it on a serving plate and serve it immediately.
Preheat the oven to 425°F. Transfer the pumpkin chunks to a large baking sheet. You can add oil and seasonings to the sheet tray itself.
Spread them evenly in a single layer and cook for about 25-30 minutes, or until golden brown around the edges (time may vary based on the size of your cubes). You may have to turn them once halfway through for even cooking.
Note: Nutrition values are my best estimates. If you rely on them for your diet, use your preferred nutrition calculator.