Summer Squash Gratin with Tomatoes and Parmesan

Introduction

Summer Squash Gratin with Tomatoes, Parmesan, and Fresh Thyme, as featured on Love With Recipes, is a celebration of the vibrant flavors and fresh ingredients that define the peak of the summer season. This dish exemplifies the art of layering seasonal vegetables—zucchini, yellow squash, and ripe tomatoes—into a luscious, golden-baked gratin that captures the essence of summer’s bounty. Its rich yet light profile makes it an ideal centerpiece for light lunches, elegant dinners, or festive gatherings. The combination of mellow, sweet squash, tangy tomatoes, and savory Parmesan cheese, enhanced with fragrant thyme, creates a harmonious blend of textures and flavors that will delight your palate and impress your guests. Carefully crafted, this gratin balances the natural moisture of the vegetables with the crispy, cheesy topping, resulting in a dish that’s both satisfying and nourishing. Perfect for those who seek a healthy, low-cholesterol, vegetarian-friendly option, this recipe leverages fresh, wholesome ingredients to produce a vibrant, nutrient-dense meal that highlights the best of summer produce.

Time

Preparation Time: 30 minutes

Cooking Time: 1 hour 10 minutes

Total Time: approximately 1 hour 40 minutes

Note: The total time includes preparation, assembly, baking, and resting time to allow flavors to meld beautifully.

Needed Equipment

• Oven preheated to 375°F (190°C)
• 2-quart shallow gratin or casserole dish (preferably oval for aesthetic presentation)
• Medium skillet or sauté pan
• Sharp knives for slicing vegetables and garlic
• Cutting board
• Measuring spoons and cups
• Small mixing bowls for tossing vegetables and cheese mixture
• Plate or draining rack for tomatoes
• Grater for Parmesan cheese (if not pre-grated)
• Kitchen brush or paper towels for oiling the dish
• Aluminum foil or baking sheet (optional, for catching drips)

Tags

• Vegetarian
• Summer vegetables
• Healthy
• Low cholesterol
• Vegetable gratin
• Oven-baked
• Seasonal produce
• Easy to prepare

Serving Size

This recipe yields approximately 6 generous servings, making it perfect for family dinners or small gatherings. Adjust portion sizes accordingly if serving as a main course or side dish.

Difficulty Level

Moderate. This recipe requires some skill in slicing vegetables evenly, layering the ingredients, and monitoring baking to achieve a golden, bubbly top. However, it is straightforward enough for home cooks with basic culinary experience.

Allergen Information

• Contains dairy (Parmesan cheese)
• Contains garlic and onions (possible allergen for sensitive individuals)

Dietary Preference

Vegetarian, suitable for low-cholesterol diets, and can be adapted for gluten-free preferences by ensuring the cheese and other ingredients are gluten-free.

Course

Main course, side dish, vegetarian entrée

Cuisine

Fresh, seasonal, American-inspired with Mediterranean influences

Ingredients

Instructions

Preheat the Oven and Prepare the Dish

Begin by setting your oven to 375°F (190°C). While it heats, prepare your gratin dish by lightly oiling the bottom and sides with a brush or a paper towel dipped in olive oil. This prevents sticking and ensures a beautiful, crispy crust on the finished gratin. If you prefer, you can also use a non-stick spray, but olive oil provides flavor and helps develop a delicious crust. Place the dish on a stable baking sheet for easy handling and to catch any drips during baking.

Cook the Aromatic Base: Onions and Garlic

In a medium skillet, heat 2 tablespoons of olive oil over medium heat. Once the oil shimmers, add the sliced onions. Cook, stirring occasionally, until the onions become translucent and start to turn a light golden color, about 5-7 minutes. This slow caramelization enhances their sweetness and adds depth to the dish. Be careful not to burn the onions; if they start to brown too quickly, reduce the heat to medium-low.

Add the minced garlic to the skillet, stirring continuously for 1-2 minutes until fragrant. The garlic should become aromatic but not burn, which can impart a bitter flavor. Remove from heat and let cool slightly before spreading in the gratin dish. This step forms the flavorful base of your gratin, providing a sweet, savory foundation for the vegetables.

Prepare the Tomatoes and Squash

While the onion and garlic mixture cools, prepare your vegetables. Place the sliced tomatoes on a shallow plate or a wire rack to drain excess juices. This step is important to prevent the gratin from becoming overly watery. If you notice a lot of liquid accumulating, discard the juices to keep the final dish firm and not soggy.

In a medium bowl, toss the zucchini and yellow squash slices with 1 1/2 tablespoons of olive oil, 2 tablespoons of finely chopped fresh thyme leaves, and 1/2 teaspoon of coarse salt. Gently coat the vegetables evenly so that each slice is flavored with herbs and seasoned appropriately. The oil helps the vegetables cook evenly and facilitates browning, while thyme adds a fragrant, earthy note that complements the other ingredients.

Assemble the Gratin Layers

Start by spooning the cooled onion and garlic mixture into the prepared gratin dish, spreading it evenly across the bottom. Sprinkle one tablespoon of fresh thyme leaves over the onion layer to infuse the entire dish with herbal aroma.

Next, arrange the tomato slices in a single layer across one end of the dish, slightly overlapping each slice to create a continuous, colorful layer. Sprinkle a portion of the grated Parmesan cheese over the tomatoes, ensuring even distribution for a cheesy, savory flavor in every bite.

Layer the zucchini slices next, overlapping each slightly over the tomatoes. Season with a pinch of freshly ground black pepper and a small pinch of coarse salt to enhance the flavor profile. Sprinkle Parmesan cheese over the zucchini layer as well, creating a cheesy barrier that will melt into the vegetables during baking.

Follow with a layer of yellow squash slices, overlapping them in the same manner, then repeat the process—tomatoes, zucchini, and squash—until the dish is full. Each layer should be lightly seasoned and topped with cheese for a harmonious blend of flavors and textures.

Bake to Perfection

Once assembled, drizzle the remaining 1 1/2 tablespoons of olive oil evenly over the top of the layered vegetables. This step ensures a crispy, golden crust. In a small bowl, combine the remaining Parmesan cheese with the last tablespoon of fresh thyme leaves and sprinkle this mixture generously over the entire gratin surface.

Place the dish in the preheated oven and bake for approximately 65-70 minutes. During this time, the vegetables will soften, juices will bubble and reduce, and the cheese topping will turn a deep golden brown. Check periodically to ensure the top doesn’t burn; if it starts to darken too quickly, loosely cover with aluminum foil.

The gratin is ready when the top is crispy, bubbling, and deeply golden, and the juices have reduced to a rich, flavorful glaze. Insert a skewer or knife into the center to check for tenderness—if the vegetables are soft and the edges are slightly caramelized, it’s time to remove from the oven.

Rest and Serve

Remove the gratin from the oven and let it rest for at least 15 minutes before serving. Resting allows the juices to redistribute and the flavors to intensify, making each bite more flavorful. Use a spatula or serving spoon to gently lift portions onto plates or serve directly from the dish for a rustic presentation.

This summer vegetable gratin pairs beautifully with fresh green salads, crusty artisan bread, or grilled proteins like fish or chicken if you desire a more substantial meal. Its vibrant colors and inviting aroma make it a centerpiece of any summer table.

Preparation Tips

• Use a mandoline slicer to achieve uniformly thin slices of zucchini, squash, and tomatoes for even cooking and attractive presentation.
• Drain the tomato slices thoroughly to prevent excess moisture from diluting the gratin or causing it to become soggy.
• Choose fresh thyme for the best flavor; dried thyme can be used but should be added in smaller quantities.
• If you prefer a slightly spicier flavor, sprinkle a pinch of red pepper flakes between layers.
• For a crispier top, broil the gratin for 2-3 minutes after baking, watching carefully to prevent burning.
• Feel free to experiment with other herbs such as basil or oregano for varied flavor profiles.

Nutritional Information

Tips and Tricks

• For added flavor, sprinkle a handful of toasted pine nuts or chopped fresh basil over the gratin before serving.
• If fresh thyme is unavailable, substitute with dried thyme or herbes de Provence for a different aromatic profile.
• Adjust salt and pepper according to your taste, especially considering the saltiness of Parmesan cheese.
• Use high-quality Parmesan cheese for a richer, more complex flavor; freshly grated cheese melts better and provides a more authentic taste.
• Ensure the vegetables are sliced uniformly for even baking and an attractive layered appearance.

Add-ons and Variations

• Sprinkle chopped fresh basil, oregano, or tarragon for different herbal accents.
• Add a layer of cooked, crumbled goat cheese or ricotta for a creamy texture.
• Incorporate thin slices of cooked ham or prosciutto for a non-vegetarian version.
• Top with breadcrumbs mixed with a little olive oil and Parmesan for an extra crispy crust.

Side Dishes

• Fresh mixed green salad with vinaigrette
• Crusty baguette or artisan bread
• Grilled chicken, fish, or shrimp for a complete meal
• Roasted or steamed seasonal vegetables
• Light fruit salad for a refreshing dessert

Improvements and Customizations

• For a vegan version, replace Parmesan with nutritional yeast or vegan cheese options.
• To make it more filling, serve with a side of quinoa or wild rice.
• Incorporate thinly sliced eggplant or bell peppers for added variety.
• Experiment with different cheese blends, such as mozzarella or fontina, for diverse melting qualities and flavors.

Save and Store

Leftovers can be stored in an airtight container in the refrigerator for up to 3 days. To reheat, place in a preheated oven at 350°F (175°C) for about 15-20 minutes or until warmed through and crispy on top. Avoid microwaving, as it can make the gratin soggy and unevenly heated. For best results, reheat in the oven to preserve the crispy cheese crust and layered textures.

If you want to prepare this dish ahead of time, assemble it up to a day in advance, cover tightly with plastic wrap, and refrigerate. Bake just before serving for optimal freshness.

FAQ

Can I make this gratin with other vegetables?

Absolutely. Sliced eggplant, bell peppers, or zucchini varieties like pattypan can be substituted or added. Just be mindful of their cooking times and moisture content.

Is this dish suitable for vegan diets?

Yes, by using vegan cheese alternatives and ensuring all ingredients are plant-based, this gratin can be completely vegan. Nutritional yeast can add a cheesy flavor if desired.

How do I prevent the gratin from becoming too watery?

Drain excess juices from the tomatoes and avoid over-slicing vegetables that release excessive moisture. Baking at a high temperature also helps evaporate liquids, resulting in a crusty top and firm interior.

Can I freeze leftovers?

Freezing is possible but may affect the texture. Wrap tightly and store in an airtight container for up to 2 months. Reheat thoroughly in the oven for best results.

Conclusion

Summer Squash Gratin with Tomatoes, Parmesan, and Fresh Thyme embodies the vibrant, fresh essence of summer produce. It’s a versatile dish that can stand alone as a main course or serve as a stunning side. The layers of colorful vegetables, fragrant herbs, and melty cheese create a harmonious blend of flavors and textures that celebrate the bounty of the season. With simple ingredients and straightforward techniques, this gratin is accessible yet impressive, making it a perfect addition to your culinary repertoire. Whether you’re hosting a summer dinner or simply craving a wholesome, satisfying vegetable dish, this gratin is sure to become a favorite. Remember to visit Love With Recipes for more inspiring, flavorful recipes that bring the joy of cooking into your life. Happy baking, and enjoy the vibrant tastes of summer in every bite!

References

• Fine Cooking: Classic Vegetable Recipes, 2021 Edition
• Seasonal Cooking: A Guide to Summer Vegetables and Herbs