1. Preheat the oven to 425 degrees F. Line a rimmed baking sheet with parchment paper and lightly coat with cooking spray.
2. In a small shallow bowl combine cheese, garlic and onion powder, salt, and pepper and stir well to combine. Place the milk in a small dish.
3. Dip each zucchini slice in milk and then in the cheese mixture. Place on the prepared baking sheet in a single layer and bake for about 30 minutes, turning once, until browned and nicely crisped.
140 calories per serving