Remove the leaves from the base of the cauliflower. Cut around the stem to remove it. Discard both the leaves and the stem.
Cut the cauliflower in half. Use your fingers to break the cauliflower into florets. Make sure to cut off any large stems - they won't crisp.
You'll need only half a head of cauliflower for this recipe. Save the remaining half of the florets for another recipe or double up this recipe.
Rinse the cauliflower florets in water and pat them dry completely.
To a large bowl, add oil, salt, garlic powder, ground black pepper, hot sauce, and melted butter till well combined. Toss in the cauliflower florets and coat them completely.
Sprinkle cornstarch over the cauliflower. Mix it gently to coat it evenly.
Place parchment paper in the air frying basket. Arrange the cauliflower florets in a single layer - don't overcrowd. Depending on the capacity of your air-fryer, you may need two or more batches. [Note: If you are using a basket-style air fryer, you can coat the basket with a cooking spray instead of using parchment paper]
Air fry for about 10 minutes at 375°F. Pause the air frying at around 5 minutes and rotate the tray to ensure even cooking. If using a basket-style air fryer, shake the basket to toss the cauliflower.
Mix melted butter with hot sauce (at room temperature). Use a brush to slather the hot sauce-butter mixtture till the florets are completely coated.
Put them back in the air fryer and air fry them for 3 minutes at 375°F.