Dice up sweet potato, russet potatoes, and onions into same sized small chunks (be sure the onion is not too small as it might burn)

Toss potatoes and onion with 2 tablespoons of olive oil, salt, pepper, garlic powder, and thyme

Transfer mixture to the air fryer basket

Turn air fryer to 400 degrees and cook for 20 - 30 minutes. Check the mixture at least 3 times. Stir and spray the top with olive oil spray if needed (I found this helps it get perfectly crisp)

Once done, hash should be crispy on the outside but not burnt