Preheat your oven to 375°F (190°C).

Dice the zucchini, eggplant, and bell peppers into bite-sized pieces, and chop the onion while mincing the garlic.

In a large skillet, heat a couple of tablespoons of olive oil over medium heat. Add the chopped onion and minced garlic, sautéing until translucent.

Add the diced zucchini, eggplant, and bell peppers to the skillet, stirring well to combine. Sauté for about 5-7 minutes until slightly tender.

Remove the skillet from the heat and mix in your chosen herbs, salt, and pepper to taste.

In a greased baking dish, layer half of the sautéed vegetable mixture across the bottom. Follow with a generous layer of cheese.

Repeat the layering process with the remaining vegetables and top with another layer of cheese.

Bake the casserole in the oven for 25-30 minutes until bubbly and golden brown.

Remove and let cool for 5-10 minutes before serving.