Combine the ricotta, mozzarella, parmesan and parsley in a medium bowl.
Season both sides of the zucchini with salt and pepper.
In a shallow plate, beat the eggs and 1 teaspoon of water together. Place the bread crumbs in another plate.
Place each zucchini round in the egg, then the breadcrumbs.
Spray a generous amount of olive oil spray on each side and transfer to the air fryer basket in an even layer, in batches as needed.
Preheat the oven to 425F.
Air fry 380F for 12 minutes turning half way, until crisp, golden and tender in the center. Set aside. Transfer to a baking sheet.
Spoon each piece with 1 generous tablespoon of sauce, then 1 tablespoon of the cheese mixture.
Bake until the cheese is melted and golden, about 5 to 6 minutes. Garnish with parsley if desired.
If you prefer to do this all in the air fryer, you can air fryer in batches 350F until the cheese is melted, about 1 to 2 minutes. Garnish with parsley if desired.
Notes
No Air Fryer, No Problem! Bake the zucchini in a preheated oven 425F on a sheet pan sprayed with oil until golden, 18 minutes flipping halfway.