Preheat oven (or an air fryer) to 425°F.
In a small bowl, combine the salt, pepper, paprika, garlic, onion powder and cornstarch; set aside.
Add the cubed sweet potatoes to a large bowl and drizzle with olive oil and the seasoning.
Stir until the sweet potatoes are evenly coated.
Spread the sweet potatoes onto a large cookie sheet.
Bake for 15 minutes then flip them over with a spatula. Bake an additional 5-10 minutes or until the sweet potatoes are soft on the inside and golden and crisp on the exterior.
