Preheat your oven to 375°F (190°C) and grease a 9x13 inch baking dish with olive oil.

In a skillet over medium heat, add olive oil, then sauté chopped onion and minced garlic for about 3–4 minutes until soft.

In a large bowl, combine sliced zucchini, corn kernels, halved cherry tomatoes, onions, and garlic; season with oregano, salt, and pepper.

Pour the vegetable mixture into the prepared baking dish, spreading it evenly.

Sprinkle mozzarella cheese over the vegetable mixture.

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

Drizzle olive oil over the breadcrumb topping and bake for 30–35 minutes until golden brown and bubbly.

Let it cool for 5–10 minutes before garnishing with fresh basil or parsley.