Preheat your air fryer to 400°F for 3–4 minutes
Peel and dice 2 large sweet potatoes, peeled and diced into ½-inch cubes into uniform ½-inch cubes. Dice 1 large bell pepper, diced into ½-inch pieces and 1 medium onion diced into ½-inch pieces to the same size.
Add all to a large bowl. Drizzle with 2 tablespoons olive oil and add 1 teaspoons garlic powder 1 teaspoons smoked paprika, 1/2 teaspoon ground cumin, 1/2 teaspoon salt, 1/3 teaspoon black pepper and 1/3 teaspoon ground cinnamon (optional) if using. Toss thoroughly until every piece is evenly coated.
Pour the seasoned mixture into the air fryer basket and spread into as close to a single layer as possible. Do not pile — crowded cubes steam instead of crisp. Cook in two batches if your air fryer is small.
Air fry at 400°F for 6–7 minutes, , then open the basket and shake or stir well to expose new surfaces to the hot air.
Continue cooking for another 6–7 minutes, then shake again. Lightly spray the top of the hash with 1 teaspoons cooking spray for finishing for maximum caramelization.
Finish and serve: Cook for a final 5–6 minutes, until the sweet potatoes are deeply golden on the outside and a fork slides in with no resistance. Garnish with fresh parsley or chives and serve immediately.