07Sprinkle half of tarragon and 1/2 cup cheese over.08Repeat layering with zucchini, tarragon and 1/2 cup cheese.09Combine milk, cream and eggs in small bowl.10Season with salt and pepper.11Pour custard mixture over zucchini.12Sprinkle remaining cheese over.13Bake until gratin is set in center, about 35 minutes.14Serve immediately.