Description
A creamy, cheesy Zucchini and Yellow Squash Au Gratin that’s rich and comforting yet light enough for any season. This American classic side dish (or main!) is perfect for family dinners, holiday gatherings, or cozy weeknight meals.
Ingredients
Scale
- 3 medium zucchinis, sliced into ¼-inch rounds
- 3 medium yellow squash, sliced into ¼-inch rounds
- 2 tablespoons olive oil
- 1 small yellow onion, finely diced
- 2 cloves garlic, minced
- 1 cup heavy cream
- 1 cup shredded sharp cheddar cheese
- 1 cup shredded Gruyère cheese
- ½ cup grated Parmesan cheese
- ¾ cup panko breadcrumbs
- 2 tablespoons butter, melted
- ½ teaspoon dried thyme
- ½ teaspoon dried oregano
- ½ teaspoon salt
- ¼ teaspoon black pepper
- ¼ teaspoon nutmeg (optional)
- Fresh parsley, for garnish
Instructions
- Preheat and Prepare:
Preheat the oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with olive oil or butter. - 2. Slice the Squash:
Slice the zucchini and yellow squash into ¼-inch thick rounds for even cooking. - 3. Sauté Onion and Garlic:
Heat olive oil in a skillet over medium heat. Add diced onion and sauté until translucent, about 5 minutes. Add minced garlic and cook for 1 minute. - 4. Layer the Vegetables:
Arrange half the zucchini and squash slices in the baking dish. Season with salt, pepper, thyme, and oregano. - 5. Make the Cheese Sauce:
In the same skillet, add the heavy cream and bring it to a simmer. Stir in half of the cheddar, Gruyère, and Parmesan until melted and smooth. Add a pinch of nutmeg if using. - 6. Assemble the Gratin:
Pour half of the cheese sauce over the first layer of squash. Add the remaining squash slices and pour the rest of the sauce on top. - 7. Prepare the Topping:
Mix the panko breadcrumbs with melted butter and the remaining Parmesan cheese. Sprinkle evenly over the dish. - 8. Bake:
Bake uncovered for 30-35 minutes, until golden and bubbly. Let cool slightly before serving. - 9. Garnish and Serve:
Sprinkle with chopped fresh parsley and serve warm.
Notes
- For a thicker gratin, lightly salt the squash slices and let them drain for 15 minutes before layering.
- Swap cheeses if desired: mozzarella, fontina, or gouda work beautifully.
- You can prepare the dish a day ahead and refrigerate it before baking.
- Prep Time: 20 minutes
- Cook Time: 35 minutes
- Category: Dinner
- Cuisine: American
Keywords: Zucchini and Yellow Squash Au Gratin, easy squash gratin, cheesy vegetable casserole, summer squash recipe, baked zucchini
