Preheat the oven to 400 degrees Fahrenheit (205 Celsius).
Heat the butter and oil in the skillet over medium/high heat. Add the zucchini and cook, stirring occasionally for 2-3 minutes. Season with half of the salt and half of the pepper. Stir well.
Add the corn, garlic, half and half, Parmesan cheese, scallions, thyme leaves, and the remaining salt and pepper. Cook, stirring occasionally for 3-4 minutes.
Transfer the zucchini and corn mixture to a baking dish that has been sprayed with cooking spray.
Top the vegetable mixture evenly with the ¼ cup Parmesan cheese, and ¼ cup bread crumbs.
Bake (uncovered) in the preheated 400-degree oven for 20 minutes or until the topping is golden brown.
Remove from the oven and allow to sit for 10-15 minutes before serving.
Notes
May be made in advance (minus the topping) and kept in the refrigerator 2 days in advance of baking. Before baking add the topping of Parmesan cheese and bread crumbs.Leftovers may be kept in the refrigerator in an airtight container for up to 5 days.Leftovers may be frozen in an airtight container for up to 2 months. Thaw in the refrigerator overnight and reheat (uncovered) in the oven, microwave, or air fryer until hot.