Preheat oven to 350°. Spray an 8X8 inch baking dish with pan spray.
Combine sliced squash, basil, green onion, thyme, garlic and ½ c mozzarella and ½ cup parmesan cheese and stir until veggies are coated with cheese and herbs are well distributed.
Season with salt and pepper. Put the mixture in the baking dish and bake uncovered for about 25-30 minutes.
When zucchini is nearly cooked through, sprinkle casserole with the remaining ½ cup of mozzarella cheese. Bake an additional 10 minutes or until the cheese is melted and nicely browned. Serve hot.