Zucchini and Yellow Squash Au Gratin

Indulge in a comforting and flavorful dish with our Zucchini and Yellow Squash Au Gratin recipe. This delightful dish combines tender zucchini and yellow squash with a creamy, cheesy sauce, baked to perfection until golden brown and bubbly. Easy to make and bursting with flavor, this gratin is sure to become a family favorite.


  • 2 medium zucchinis, sliced into rounds
  • 2 medium yellow squash, sliced into rounds
  • 2 tablespoons butter
  • 2 tablespoons all-purpose flour
  • 1 cup milk
  • 1 cup shredded cheddar cheese
  • 1/4 cup grated Parmesan cheese
  • Salt and pepper to taste
  • 1/4 cup breadcrumbs (optional)
  • Fresh parsley, chopped, for garnish


  1. Preheat the oven to 375°F (190°C) and grease a baking dish with butter or cooking spray.
  2. In a large skillet, melt the butter over medium heat. Add the flour and cook, stirring constantly, for 1-2 minutes to make a roux.
  3. Gradually whisk in the milk until smooth and thickened.
  4. Stir in the cheddar cheese and Parmesan cheese until melted and smooth. Season with salt and pepper to taste.
  5. Add the sliced zucchini and yellow squash to the cheese sauce, tossing to coat evenly.
  6. Transfer the zucchini and squash mixture to the prepared baking dish, spreading it out evenly.
  7. If desired, sprinkle breadcrumbs over the top of the gratin for added crunch.
  8. Bake in the preheated oven for 25-30 minutes, or until the vegetables are tender and the top is golden brown and bubbly.
  9. Garnish with chopped parsley before serving.

Serving Tips:

  1. Serve the Zucchini and Yellow Squash Au Gratin as a flavorful side dish alongside roasted chicken, grilled steak, or baked fish for a complete meal.
  2. Garnish each serving with freshly chopped parsley for a pop of color and added freshness.
  3. Pair this gratin with a crisp green salad dressed with vinaigrette to balance out the richness of the cheesy sauce.
  4. For a brunch or breakfast option, serve this gratin alongside scrambled eggs or a frittata for a satisfying start to the day.
  5. Consider adding a sprinkle of red pepper flakes or a dash of hot sauce for a spicy kick if desired.

Storage Tips:

  1. Store any leftover Zucchini and Yellow Squash Au Gratin in an airtight container in the refrigerator for up to 3-4 days.
  2. Reheat individual portions in the microwave or oven until warmed through before serving.
  3. To maintain the crispness of the breadcrumb topping, store any leftovers separately and sprinkle over the gratin just before reheating.
  4. You can also freeze this gratin for longer-term storage. Place cooled individual portions in freezer-safe containers or wrap tightly with plastic wrap and aluminum foil. Freeze for up to 2-3 months.
  5. Thaw frozen gratin overnight in the refrigerator before reheating. Bake in the oven until heated through, ensuring the vegetables are tender and the topping is crispy.

By following these serving and storage tips, you can enjoy the delicious flavors of Zucchini and Yellow Squash Au Gratin any time while ensuring its freshness and optimal taste.


  1. Herb Infusion: Enhance the flavor profile by adding fresh or dried herbs such as thyme, rosemary, or basil to the cheese sauce before baking.
  2. Mushroom Medley: Incorporate sautéed mushrooms into the gratin for an earthy depth of flavor and added texture.
  3. Protein Boost: Add cooked bacon, diced ham, or shredded rotisserie chicken to the gratin for a heartier dish that’s perfect for a main course.
  4. Tomato Twist: Layer sliced tomatoes between the zucchini and yellow squash for a colorful variation. Sprinkle with Italian seasoning and mozzarella cheese for a caprese-inspired twist.
  5. Spinach Surprise: Mix chopped spinach into the cheese sauce for an extra dose of greens and nutrients. This variation adds a vibrant color and a mild spinach flavor.
  6. Spicy Kick: Add diced jalapeños or green chilies to the gratin for a spicy twist. Top with pepper jack cheese for an extra kick of heat.
  7. Artichoke Addition: Incorporate chopped artichoke hearts into the gratin for a unique flavor and texture. This variation pairs well with Parmesan cheese and lemon zest.
  8. Grilled Veggie Option: Instead of baking the zucchini and yellow squash, grill them until tender and charred before assembling the gratin. This adds a smoky flavor to the dish.
  9. Vegan Version: Substitute dairy-free butter, milk, and cheese alternatives for a vegan-friendly option. Nutritional yeast can be used to add a cheesy flavor to the sauce.
  10. Ratatouille-Inspired: Layer slices of zucchini, yellow squash, eggplant, and tomatoes in a baking dish. Top with the cheese sauce and bake until tender for a flavorful twist on the classic French dish.
  11. Greek-Inspired: Add kalamata olives, diced tomatoes, and crumbled feta cheese to the gratin for a Mediterranean twist. Sprinkle with dried oregano and a drizzle of olive oil before baking.
  12. Cheesy Broccoli Blend: Mix steamed broccoli florets into the cheese sauce for a nutritious addition. Top with extra cheddar cheese and buttery crackers for a crunchy topping.
  13. Tex-Mex Fusion: Layer sliced jalapeños, black beans, corn kernels, and diced bell peppers between the zucchini and yellow squash. Top with pepper jack cheese and crushed tortilla chips for a Southwestern flair.
  14. Caramelized Onion Elegance: Sauté thinly sliced onions until caramelized and layer them between the zucchini and yellow squash. Top with Gruyere cheese and breadcrumbs for an elevated twist.
  15. Italian-Inspired: Add roasted red peppers, sliced black olives, and diced Italian sausage to the gratin for a hearty and flavorful dish. Sprinkle with Italian seasoning and mozzarella cheese before baking.

FAQs :

  1. Can I use frozen zucchini and yellow squash for this recipe? While fresh produce is recommended for the best texture and flavor, you can use frozen zucchini and yellow squash if that’s what you have on hand. Be sure to thaw and drain them well before using.
  2. Can I make this gratin ahead of time? Yes, you can assemble the gratin up to a day in advance and store it in the refrigerator. Simply bake it when ready to serve, adding a few extra minutes to the baking time if needed.
  3. Can I use different types of cheese in the sauce? Absolutely! Feel free to experiment with different cheeses such as gruyere, fontina, or Monterey Jack to customize the flavor of the gratin.
  4. How can I make this dish gluten-free? Use gluten-free all-purpose flour and breadcrumbs or omit the breadcrumbs altogether for a gluten-free version of this gratin.
  5. Can I add other vegetables to the gratin? Yes, you can customize this recipe by adding other vegetables such as bell peppers, onions, or carrots. Just be sure to adjust the cooking time accordingly.
  6. What can I serve with this gratin? This gratin pairs well with a variety of dishes including roasted meats, grilled fish, or a simple green salad for a complete meal.
  7. Can I freeze leftovers of this dish? Yes, you can freeze leftovers of this gratin for up to 2-3 months. Just be sure to wrap it tightly or store it in an airtight container to prevent freezer burn.
  8. How do I reheat the gratin? Reheat individual portions in the microwave until warmed through, or bake the entire gratin in the oven at 350°F (175°C) until heated through.
  9. Can I make this dish dairy-free? Yes, you can use dairy-free alternatives such as plant-based milk, butter, and cheese to make this gratin dairy-free.
  10. What size baking dish should I use? A 9×13 inch baking dish or similar size is recommended for this recipe. Adjust the quantities accordingly if using a smaller or larger dish.

Enjoy this comforting Zucchini and Yellow Squash Au Gratin as a side dish or a delicious vegetarian main course. With its creamy cheese sauce and tender vegetables, it’s sure to be a hit at any meal!