Zucchini Tomato Gratin is a simple, elegant side dish that works equally well for a weeknight meal or a holiday table. Thin slices of zucchini, potato, and tomato are arranged in alternating rows and baked with olive oil, tomato sauce, garlic, and Italian seasonings until tender and bubbly.
An Easy and Healthy Baked Veggie Recipe
If you love uncomplicated vegetable dishes that look as good as they taste, this gratin is a winner. With just three main vegetables and minimal prep—mostly slicing—you get a colorful, flavorful dish with classic Mediterranean flavors. The red, green, and white layers are accented by a simple tomato sauce seasoned with garlic, olive oil, and Italian herbs. A sprinkle of parmesan and a brief finish under the oven makes a light golden topping.
This gratin is forgiving and versatile: adjust seasonings, swap potatoes for a different variety, or add onions for extra sweetness. It’s an excellent way to showcase fresh summer produce.
What You’ll Need
This recipe uses a short list of common ingredients. Choosing good-quality tomato sauce and fresh vegetables will give the best results.
- Tomato sauce: about 1 cup; strained tomatoes can substitute.
- Garlic: 4 cloves, minced (or 1 teaspoon garlic powder if short on time).
- Olive oil: divided—one tablespoon for the sauce and remaining for drizzling.
- Italian seasoning: divided between the sauce and the vegetables.
- Tomatoes: 3–4, sliced 1/4-inch thick; roma or vine tomatoes work well.
- Zucchini: 2 small, sliced 1/4-inch thick (peeling optional).
- Potatoes: 3–4 small, Yukon Gold preferred, sliced 1/8-inch thick.
- Salt and pepper: to taste.
- Parmesan: 1/2 cup shredded for a savory finish.
- Fresh parsley: chopped, for garnish.
How to Make Zucchini Tomato Gratin
The dish’s visual appeal comes from the neat rows of overlapping vegetables. Follow these steps for a reliable result.
- Preheat and prep the sauce. Preheat your oven to 375°F. In the bottom of a 2-quart baking dish, stir together the tomato sauce, minced garlic, 1 tablespoon olive oil, and 1 teaspoon Italian seasoning.
- Arrange the vegetables. Stand the slices upright in the dish, alternating tomato, zucchini, and potato. Pack them snugly so the dish is filled. Sprinkle with the remaining Italian seasoning, salt, and freshly ground black pepper, then drizzle with the remaining olive oil.
- Bake. Cover the dish with aluminum foil and bake for about 35 minutes. Remove the foil, sprinkle the top with shredded parmesan, and return the gratin to the oven uncovered. Continue baking 20–30 minutes more, until the vegetables are tender and the top is bubbly and lightly browned.
- Rest and serve. Remove from the oven and let stand for 10 minutes. Garnish with chopped parsley and serve warm.
Tips for Success
Some practical tips to improve your gratin:
- Onions: Add diced or caramelized onions for extra depth—either layered with the vegetables or stirred into the sauce.
- Crunchy topping: Mix breadcrumbs or panko with the parmesan for a crisp finish.
- Watch cook time: Ovens and slice thickness vary. Check tenderness with a fork and adjust baking time as needed.
- Slicing tool: A mandoline speeds up slicing and ensures even thickness; use caution as blades are sharp.
What to Serve with Zucchini Tomato Gratin
This gratin pairs well with roasted or grilled proteins such as chicken, pork, or turkey. It also complements vegetarian mains or can be served alongside a green salad for a lighter meal.
Can I Freeze Zucchini Tomato Gratin?
- Freezing is not recommended. The high-water content of zucchini, tomatoes, and potatoes can lead to a watery, mushy texture after thawing.
How to Store and Reheat Leftovers
- To refrigerate: cover the casserole tightly with plastic wrap or transfer portions to airtight containers. Store for 3–4 days.
- To reheat: warm in a 375°F oven until heated through, which helps restore some crispness to the top.
ENJOY!
Zucchini Tomato Gratin
Ingredients
- 1 cup tomato sauce
- 4 cloves garlic, minced
- 2 tablespoons olive oil, divided
- 2 teaspoons Italian seasoning, divided
- 3 to 4 tomatoes, sliced ¼-inch thick
- 2 small zucchini, sliced ¼-inch thick
- 3 to 4 small Yukon Gold potatoes, sliced 1/8-inch thick
- Salt and freshly ground black pepper, to taste
- ½ cup shredded parmesan cheese
- Chopped fresh parsley, for garnish
Instructions
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Preheat oven to 375°F.
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In a 2-quart baking dish, combine tomato sauce, garlic, 1 tablespoon olive oil, and 1 teaspoon Italian seasoning.
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Arrange sliced vegetables upright in alternating rows, fitting them tightly in the dish.
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Season with remaining Italian seasoning, salt, and pepper, then drizzle with the remaining olive oil.
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Cover with foil and bake for about 35 minutes.
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Remove foil, sprinkle with parmesan, and bake uncovered another 20–30 minutes until vegetables are tender and the top is bubbly.
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Let rest 10 minutes, garnish with parsley, and serve.
Notes
Nutrition
Nutritional info is an estimate and provided as a courtesy. Values may vary according to ingredients and tools used.
More Vegetarian Recipes
- Cheese Tortellini with Roasted Tomatoes
- Cheesy Zucchini and Squash Casserole
- Black Beans and Corn Stuffed Portobello Mushrooms