Zucchini Rice Gratin

Zucchini Rice Gratin greets you with a golden crust, tender vegetable layers, and a rich, savory aroma that fills the kitchen. You get crisp edges, soft rice pockets, and bright tomato sweetness in every forkful. This dish tastes fresh, feels comforting, and cooks without fuss, so you can make it on a weeknight or bring it to a potluck. Serve it warm with a simple salad, or pair it with a roasted protein; for example, you can balance the meal by serving it alongside oven-baked chicken and rice for a hearty family dinner. Overall, Zucchini Rice Gratin gives you straightforward steps, bold flavor, and satisfying texture.

Why Make Zucchini Rice Gratin

You save time because it uses cooked rice and a quick roast step. Therefore, you finish the dish faster than a traditional casserole.

You enjoy balanced flavors: sweet tomatoes, fragrant thyme, and nutty Parmesan. Also, the texture contrast keeps each bite interesting.

You cut costs by using seasonal zucchini and pantry staples. Thus, the dish stays budget-friendly without losing flavor.

You get a versatile side or main. For example, you can serve it vegetarian or add a protein on the side for a complete meal.

How to Make Zucchini Rice Gratin

First, you roast the zucchini and tomatoes to concentrate their flavor and add caramelized notes. Then, you sauté the onion and garlic until soft to build a savory base. Next, you mix those elements with cooked rice, eggs, thyme, and half of the Parmesan to bind everything together.

After that, you layer the rice mixture and roasted zucchini in a buttered dish, top with roasted tomatoes and the remaining cheese, and bake until golden and set. Meanwhile, the oven browns the top and the eggs hold the gratin together, giving you a firm yet creamy interior. If you want another rice-bake idea, check this variation inspired by Portuguese-style rice and chicken for technique tips.

Ingredients

For the gratin:

• 1/3 cup uncooked white rice
• 5 tablespoons olive oil
• 1 1/2 pounds zucchini, sliced 1/4-inch thick
• 1/2 pound plum tomatoes, sliced 1/4-inch thick
• Table salt
• Freshly ground black pepper

For the filling:

• 1 medium onion, halved and thinly sliced
• 3 garlic cloves, minced
• 2 large eggs, lightly beaten
• 1 teaspoon chopped fresh thyme leaves
• 1/2 cup grated Parmesan cheese, divided exactly as provided

Directions

1. Preheat the oven to 450 degrees F.
2. Cook the rice according to your preferred method.
3. Meanwhile, coat baking sheets with 1 tablespoon olive oil and spread the sliced zucchini and sliced tomatoes in a single layer.
4. Season the vegetables with table salt and freshly ground black pepper.
5. Roast the tomatoes for 10 minutes, until the skins blister and the flesh softens; flip once halfway.
6. Roast the zucchini for 20 minutes, until the edges brown and the centers become tender; flip once halfway.
7. In a skillet, heat 5 tablespoons olive oil over medium heat.
8. Add the halved, thinly sliced onion, minced garlic, and a pinch of table salt; cover and cook until the onion becomes tender and translucent, about 8 minutes.
9. Combine the cooked onion mixture with the cooked rice, the lightly beaten eggs, 1 teaspoon chopped fresh thyme leaves, and half of the 1/2 cup grated Parmesan cheese.
10. Coat a 9×9-inch baking dish with a little olive oil.
11. Add half of the rice mixture to the dish and spread it into an even layer.
12. Layer half of the roasted zucchini over the rice.
13. Repeat by adding the remaining rice mixture and then the remaining roasted zucchini.
14. Top the gratin with the roasted tomatoes and sprinkle the remaining Parmesan cheese evenly.
15. Bake the gratin at 450 degrees F until it sets and the top turns golden brown, about 20 minutes.
16. Let the gratin rest for 5 minutes before serving so the layers firm up.

How to Serve Zucchini Rice Gratin

Serve warm as a vegetarian main with a crisp green salad and lemon vinaigrette. Also, offer crusty bread to soak up any creamy pockets.

Present it as a side with grilled or roasted chicken for a balanced plate. Garnish with extra thyme leaves and a drizzle of olive oil for shine.

Serve in shallow bowls to show the roasted tomato top. For a crowd, cut into squares and plate with microgreens for color.

How to Store Zucchini Rice Gratin

Refrigerator: Cool to room temperature, then store in an airtight container for up to 4 days. Reheat individual portions in a covered microwave-safe dish or in a 350°F oven until hot.

Freezer: Freeze assembled, unbaked gratin wrapped tightly in foil for up to 2 months; thaw overnight in the refrigerator before baking. Alternatively, freeze baked portions in freezer-safe containers for up to 2 months.

Reheating: For best texture, reheat in a 350°F oven covered with foil for 15–20 minutes, then uncover and bake 5 minutes to refresh the crust.

Tips to Make Zucchini Rice Gratin

• Use day-old rice or let fresh rice cool slightly so the grains hold shape and don’t turn mushy.
• Substitute Pecorino or Asiago for Parmesan if you want a sharper flavor.
• If zucchini release a lot of water, pat slices dry before roasting to get better browning.
• Save time by slicing vegetables with a mandoline for even thickness.
• Beat the eggs well and mix quickly with hot rice so they bind the dish evenly.
• Toast the Parmesan lightly before topping for extra nutty flavor.

Variations

Mediterranean Twist: Add chopped kalamata olives and a sprinkle of oregano to the rice mix for briny depth.

Herbed Summer Gratin: Fold in chopped basil and parsley after baking for a fresh herbal lift.

Cheesy Mushroom Add-In: Sauté sliced mushrooms with the onions and garlic and add them to the rice for an earthier version.

FAQs

Q: Can I use brown rice instead of white? A: Yes, you can, but brown rice needs longer cooking time; cook it fully before assembling so the gratin finishes evenly.

Q: How do I prevent a watery gratin? A: Roast zucchini until nicely browned and pat them with paper towels to remove excess moisture before layering.

Q: Can I make this ahead? A: Yes, you can assemble the gratin up to a day ahead, cover, and refrigerate; then bake just before serving for best texture.

Q: Can I omit the eggs for a vegan version? A: You can try a flax egg substitute or a thick plant-based yogurt to help bind the filling, but texture will change slightly.

Q: Will the gratin reheat well for leftovers? A: Yes, reheat in the oven to restore the crisp top; microwaving works but gives softer edges.