In a large bowl, toss zucchini with baking mix until well coated. Add beaten eggs, melted butter, and Parmesan and mozzarella cheeses. Using a large spoon or your hands, work mixture together until well blended. Add onion, garlic, oregano, parsley, salt, and pepper, and mix again. Spread mixture into a 13x9 inch baking pan.
Bake in the preheated oven for 30 minutes, or until a toothpick inserted in the center comes out clean and top is golden brown. Serve warm or at room temperature.
