Summer Zucchini and Tomato Gratin with Parmesan

This Summer Zucchini and Tomato Gratin layers tender zucchini and ripe tomatoes, finished with a crispy, cheesy herb topping and baked until golden—an easy, flavorful summer side dish everyone will enjoy.

Summer isn’t over until you say it is—and that means making the most of peak zucchini season. This zucchini and tomato gratin is a simple, elegant way to showcase fresh summer produce. It comes together quickly, makes a beautiful side for grilled meats or a vegetarian main for a light meal, and scales easily for a crowd. The combination of thinly sliced zucchini and Roma tomatoes, a drizzle of olive oil, a blend of pantry spices, and a crunchy parmesan-panko topping creates a dish that’s both comforting and bright.

Use this recipe to use up any extra garden produce—slices of yellow squash, eggplant, or bell peppers can be swapped in or added for variety. The gratin is forgiving: slice the vegetables uniformly so they cook evenly, season well, and bake until the vegetables are tender and the topping is lightly browned. Fresh basil added at the end brings a fragrant, summery finish.

Ingredients you’ll need for this zucchini tomato gratin

• 2 medium zucchini, sliced into even rounds
• 4–5 Roma (plum) tomatoes, sliced into rounds
• 2 Tbsp olive oil
• 1 tsp garlic powder
• 1 tsp onion powder
• 1 tsp Italian seasoning
• Salt and freshly ground black pepper, to taste
• 1/3 cup grated Parmesan cheese
• 1/4 cup panko breadcrumbs
• Fresh basil leaves, optional, for garnish

How to make Summer Zucchini and Tomato Gratin

Prepare the vegetables by slicing them into uniform, thin rounds. For the quickest, most consistent slices use a mandolin or a very sharp knife. If you don’t have a mandolin, take your time and slice evenly by hand. Even slices ensure the vegetables cook through at the same rate.

1. Preheat the oven to 375°F (190°C).
2. Lightly coat an 8×8-inch baking dish (or a similar-sized oval dish) with cooking spray or a thin layer of olive oil.
3. Arrange the zucchini and tomato slices in the dish, alternating them in a single overlapping row or stacked rings so the veggies are evenly distributed.
4. Drizzle the arranged vegetables with the olive oil. Sprinkle garlic powder, onion powder, Italian seasoning, salt, and pepper evenly over the top.
5. Combine the grated Parmesan and panko breadcrumbs in a small bowl, then sprinkle the mixture over the seasoned vegetables to form a crunchy, cheesy topping. Cover the dish loosely with foil.
6. Bake for 25–30 minutes, until the vegetables are tender. Remove the foil and bake an additional 8–10 minutes, or until the top is golden and crisp.
7. Remove from the oven, let rest for a few minutes, then garnish with torn fresh basil if desired. Serve warm.

Prep time is minimal—about 5 minutes if your slicing is quick—and total time is roughly 30 minutes, making this gratin a reliable weeknight side. It serves approximately 6 as a side dish.

Tips, variations and serving ideas

• Swap or add vegetables: Yellow squash, thinly sliced eggplant, or sliced bell peppers all work well in this gratin.
• Make it heartier: Stir a few tablespoons of ricotta or goat cheese between layers, or add a handful of shredded mozzarella for extra melty goodness.
• Gluten-free option: Replace panko with gluten-free breadcrumbs or crushed nuts for a crunchy topping.
• Herbs and aromatics: Fresh oregano or thyme pair wonderfully with the tomatoes and zucchini if you don’t have basil on hand.
• Serving suggestions: Pair with grilled chicken or fish, serve alongside roasted meats, or present it as a vegetarian main with crusty bread or a simple grain salad.

Nutrition (approximate)

Serving: 1/6 of recipe • Calories: 120 kcal • Carbohydrates: 12.7 g • Protein: 3.5 g • Fat: 1.3 g • Saturated Fat: 0.7 g • Sodium: 174 mg • Fiber: 2.3 g • Sugar: 4.2 g

Nutrition information is automatically calculated and should be considered an approximation.

This Summer Zucchini and Tomato Gratin is an easy, crowd-pleasing way to celebrate late-summer produce. It’s simple enough for a weeknight and elegant enough for entertaining. If you make it, consider leaving a review or sharing your photos on social media using the hashtag #eatyourselfskinny—I love seeing how you customize recipes!