Preheat your oven to 375°F (190°C).

Generously grease your 9x13-inch baking dish with olive oil or butter.

In a skillet, heat olive oil over medium heat. Sauté chopped onion and minced garlic for about 3-4 minutes.

In a mixing bowl, combine sliced zucchini, corn kernels, halved cherry tomatoes, and sautéed onion and garlic. Season with oregano, salt, and black pepper.

Spread the vegetable mixture evenly in the greased baking dish.

Sprinkle a layer of mozzarella cheese over the vegetable mixture.

In a bowl, mix grated Parmesan cheese with panko breadcrumbs and sprinkle over the mozzarella layer.

Drizzle olive oil over the breadcrumb topping.

Bake for 30-35 minutes until the topping is golden brown and cheese is bubbling.

Let it cool for 5-10 minutes before serving.

Garnish with fresh basil or parsley before serving.