Wash, trim the ends, and slice your summer squash into ½-inch-thick rounds or half-moons.
Season the sliced summer squash by adding it to a bowl. Drizzle the olive oil over the top, season with salt, garlic powder, and Italian seasoning. Toss to combine and distribute the seasonings. If using Parmesan cheese, add it now, and toss to combine.
Cook:
Place the summer squash inside the air fryer basket with the tray inside. This allows the hot air to circulate around the squash. Arrange it in a single layer with some overlap.
Cook it for a total of 7 to 9 minutes, opening the basket after 5 minutes to gently shake the contents, and then finish cooking. Add a minute or two more if your basket is a bit crowded or if your squash rounds are on the thick side.