Preheat the oven to 425°F. Spray a large baking sheet with cooking spray and set aside.
Wash and cut your zucchini into ½ inch x 3 ½ inch slices. Spread on paper towels and lightly pat to soak up some of the moisture.
In a shallow dish, combine breadcrumbs, salt, garlic powder, onion powder, paprika and black pepper*. In a separate shallow bowl, whisk the egg whites until foamy.
Working in batches, use one hand to toss the zucchini slices in the egg whites, coating evenly. Let any excess drip off. Use the other hand to toss the zucchini slices in the breadcrumb mixture, coating evenly. Shake off any excess and transfer to the prepared baking sheet so the slices are close together but not touching.
Bake for 10 minutes, then lightly spray the zucchini slices with cooking spray (this is optional, but helps them get a little crispier), and bake for an additional 15-20 minutes until golden and crisp.
While the zucchini slices are baking, combine all ingredients for the garlic aioli in a small bowl and whisk to combine. Serve the zucchini slices while warm with the garlic aioli.
Notes
*If adding parmesan cheese, add 2 Tablespoons parmesan cheese to the breadcrumbs mixture.