1. Preheat the oven to 425°F (220°C). Line a rimmed baking sheet or 9×13-inch pan with parchment paper and lightly coat it with cooking spray.

2. Grate the zucchini on the large holes of a box grater into a clean kitchen towel or several layers of paper towel. Sprinkle with the salt, let sit 5 minutes, then squeeze firmly over the sink to remove as much liquid as possible.

3. In a large mixing bowl, combine the drained zucchini, 1/2 cup of the shredded mozzarella, 1/3 cup grated Parmesan, egg, flour, garlic powder, Italian seasoning, and black pepper. Stir until the mixture is thick, sticky, and evenly combined.

4. Transfer the zucchini mixture to the prepared pan and press it into an even rectangle about 1/4-inch thick, making sure there are no thin spots.

5. Bake the crust for 12 to 15 minutes, or until the edges look set and the top is just beginning to turn light golden.

6. While the crust bakes, stir the melted butter and minced garlic together in a small bowl.

7. Remove the pan from the oven and brush the garlic butter evenly over the hot crust. Sprinkle with the remaining 1/2 cup shredded mozzarella and the additional 2 tablespoons Parmesan.

8. Return the pan to the oven and bake for another 8 to 10 minutes, or until the cheese is fully melted, bubbly, and browned in spots. For extra color, broil for 1 to 2 minutes, watching closely to avoid burning.

9. Let the cheesy zucchini breadsticks cool for about 5 minutes, then use the parchment to lift them from the pan. Slice into strips or rectangles with a sharp knife or pizza cutter.

10. Sprinkle the breadsticks with chopped fresh parsley and serve warm with marinara or pizza sauce for dipping.