Heat the olive oil in a large skillet over medium heat. Add in the onions and sauté for 2-3 minutes. Transfer the onions to a LARGE bowl and set aside. Next, add in the zucchini and sauté for 5-7 minutes or until they softens - you may need to add a drop more oil if they're dry. Transfer zucchini to the same bowl. Next add in the parmesan, breadcrumb, salt, garlic powder, onion powder, Italian herb blend, mozzarella, ham, eggs, pepper and mix until well combined.
Transfer mixture to a 7x11 inch baking dish and spread out evenly. Sprinkle with a little more breadcrumb, parmesan and Italian herb blend. Bake for 25-30 minutes - i turned on the broiler at the end to give it a tan - only 1 or 2 minutes.