In a medium bowl, combine the part-skim ricotta cheese, shredded mozzarella, grated Pecorino Romano, and finely chopped fresh parsley. Mix well until the cheeses and herbs are evenly distributed. Set the mixture aside; this will be used to top the zucchini rounds later. Sometimes I like to add an extra sprinkle of black pepper to the cheese mixture for a bit more flavor.

Lay the twelve 1/2-inch thick zucchini slices on a work surface. Season both sides of each slice with kosher salt and freshly ground black pepper. In a shallow plate, beat the eggs with 1 teaspoon of water. Place the seasoned breadcrumbs on another plate. Dip each seasoned zucchini slice first into the egg mixture, allowing any excess to drip off, then press into the breadcrumbs to evenly coat both sides. Arrange the breaded zucchini on a tray as you work through all the slices.

Spray each breaded zucchini slice generously with olive oil spray on both sides. To air fry, arrange them in a single layer inside the air fryer basket (cook in batches if necessary) and air fry at 380°F for about 12 minutes, flipping halfway through, until the outside is crisp and golden and the zucchini is tender inside. Alternatively, to use the oven, place the breaded, oiled zucchini slices on an oiled sheet pan and bake in a preheated oven at 425°F until golden and tender, about 18 minutes, flipping halfway. For best crispness, make sure you don't crowd the pan. Once cooked, transfer to a baking sheet.

Spoon about one generous tablespoon of hot marinara sauce onto each cooked zucchini round. Then, top each one with about one tablespoon of the cheese mixture from Step 1, spreading it gently to mostly cover the sauce. For a more robust flavor, I like to warm the marinara sauce before spooning it over the zucchini so the cheese melts more evenly in the next step.

Return the topped zucchini rounds to the oven and bake at 425°F for 5 to 6 minutes, or until the cheese is melted, bubbly, and golden in spots. Alternatively, you can finish them in the air fryer at 350°F for 1 to 2 minutes for the same effect. Garnish the finished zucchini rounds with a sprinkle of additional fresh parsley and, if desired, another spoonful of marinara sauce before serving. I like to let these cool for a couple of minutes so the cheese sets slightly and they’re easier to handle.