Prep the oven or air fryer. For the oven, preheat to 425°F (220°C) and line a large baking sheet with parchment. Lightly mist with cooking spray. For an air fryer, preheat to 375°F (190°C) and spray the basket.

Slice the zucchini evenly. Cut the zucchini into thin rounds, about 1/8 inch thick. A mandoline gives the most even slices, but a sharp knife works if you’re careful.

Draw out moisture. Lay the slices on a clean kitchen towel or paper towels. Sprinkle lightly with salt and let sit for 10 minutes. Pat both sides very dry. This step is key for crisp chips.

Season and oil. In a large bowl, toss the zucchini with olive oil until lightly coated. Mix the Parmesan, garlic powder, onion powder, smoked paprika, salt, and pepper in a separate bowl.

Coat with Parmesan mix. Add the Parmesan mixture to the oiled zucchini and toss to coat. Press gently so the cheese clings to each slice. Don’t overload—thin, even coverage crisps better than thick piles.

Arrange in a single layer. Spread slices on the lined baking sheet or in the air fryer basket. Keep them from touching so air can circulate. Work in batches if needed.

Bake or air fry. Oven: Bake 14–18 minutes, rotating the pan halfway, until edges are deep golden and centers are crisp. Air fryer: Cook 8–12 minutes, shaking the basket or flipping once, until crunchy.

Cool to finish crisping. Transfer chips to a wire rack as soon as they’re done. They firm up more as they cool. Taste and add a pinch of salt if needed.

Serve. Enjoy plain or with your favorite keto-friendly dip. They’re best within an hour of cooking for peak crunch.