1-Preheat the oven to 425°F: Preheat the oven to 425°F. Line a rimmed baking sheet with high-heat-resistant parchment paper and coat it with olive oil spray.
2-Slice the zucchini into 1/8-inch-thick rounds: Slice the zucchini into 1/8-inch-thick rounds.
3-Arrange the zucchini rounds on paper towels: Arrange the zucchini rounds on paper towels. Sprinkle them with salt and let them stand at room temperature for 30 minutes to draw out excess water. After 30 minutes, blot them thoroughly dry with paper towels to remove the surface water and some of the salt. There’s no need to rinse them.
4-Arrange the zucchini slices in a single: Arrange the zucchini slices in a single layer on the prepared baking sheet. Spray them with olive oil. Bake them for 15 minutes.
5-Remove the baking sheet from the oven: Remove the baking sheet from the oven. Sprinkle the zucchini slices with black pepper, garlic powder, and grated Parmesan. There’s no need to flip the zucchini.
6-Return the pan to the oven and: Return the pan to the oven and continue baking until the zucchini slices are browned and crisp, 15-20 more minutes. They won’t all crisp at the same time, so check them every 5 minutes, remove the ones that are ready to a plate, and keep baking the ones that are still soft.
7-Serve immediately: Serve immediately.