Zucchini Au Gratin Recipe

healthy zucchini au gratin in an orange baking dish

5 from 1 reviews

The Parmesan and breadcrumb toppings add a delicious, golden-crispy topping to this healthy Zucchini Au Gratin recipe.


  • 2 cloves garlic, minced
  • 2 tablespoons extra-virgin olive oil, divided
  • 1 teaspoon dried thyme
  • 3 medium zucchini, thinly sliced
  • 1/4 teaspoon salt
  • 1/4 teaspoon freshly ground pepper
  • 1/2 cup breadcrumbs*
  • 1/2 cup grated Parmesan cheese


  1. Position one oven rack on the lower third shelf and preheat to 450F. Grease a 9 x 13-inch baking dish with olive oil or cooking spray. 
  2. In a large bowl, combine the garlic, 1 tablespoon of oil, thyme, salt, and black pepper. Add the zucchini and toss to coat with the seasonings. 
  3. Transfer to the greased baking dish and bake for 15 minutes or until the zucchini is softened. 
  4. Meanwhile, in a medium bowl, combine the breadcrumbs, Parmesan, and remaining oil. Whisk until the breadcrumbs are dampened and crumbly. 
  5. Using oven mitts, remove the baking dish from the oven and sprinkle the topping over the zucchini. Bake for an additional 15 minutes or until the topping is crisp. 



Swap the regular breadcrumbs for gluten-free breadcrumbs of any kind.