Summer Squash Gratin: A Taste of Sunshine

My grandmother’s garden was a sprawling tapestry of greens and golds, and her summer squash gratin was the star of every August family gathering. I remember the first time I helped her slice the delicate squash, the sun warm on my back, the air thick with the scent of oregano and garlic. That gratin, bubbling and golden brown, was more than just a dish; it was summer on a plate, a symbol of family, and a memory I cherish. This recipe captures that same essence, bringing a touch of sunshine to your table.

Recipe Overview

• Prep Time: 25 minutes
• Cook Time: 40-50 minutes
• Total Time: 1 hour 5 minutes – 1 hour 15 minutes
• Servings: 8
• Dietary Type: Vegetarian

Ingredients

• Zest of 1 lemon
• 1 1/2 lbs summer squash or zucchini, cut into 1/6th-inch slices
• 1/2 teaspoon fine grain sea salt (for salting the squash)
• Oregano Sauce:
  • 1/4 cup fresh oregano leaves
  • 1/4 cup fresh Italian parsley
  • 1 large garlic clove, chopped
  • 1/4 teaspoon fine grain sea salt (for the sauce)
  • 1 pinch red pepper flakes
  • 1/2 cup extra virgin olive oil
• Bread Crumbs:
  • 1/4 cup unsalted butter
  • 2 cups fresh breadcrumbs (whole wheat)
• 1/2 lb Yukon gold potato, sliced transparently thin
• 3/4 cup grated Gruyere cheese, grated on a box grater

Equipment Needed

• 9×9 inch gratin pan (or equivalent baking dish)
• Colander
• Food processor or hand blender
• Small saucepan
• Large mixing bowl
• Box grater

Instructions

1. Preheat oven to 400°F (200°C) and place a rack in the middle. Rub a 9×9 gratin pan (or equivalent baking dish) with a bit of olive oil, sprinkle with lemon zest, and set aside. The lemon zest perfumes the gratin from the bottom up!

2. Place the zucchini slices into a colander placed over a sink, toss with the 1/2 teaspoon sea salt, and set aside for 10-15 minutes to drain a bit. This step is crucial for drawing out excess moisture from the squash, preventing a soggy gratin.

3. Make the oregano sauce by pureeing the oregano, parsley, garlic, 1/4 teaspoon salt, red pepper flakes, and olive oil in a food processor or using a hand blender. The sauce should be vibrant green and fragrant. Set aside.

4. Make the breadcrumbs by melting the butter in a small saucepan over medium heat. Cook for a few minutes until the butter is wonderfully fragrant, and has turned brown. Watch it carefully; browned butter can quickly turn burnt! Wait two minutes, then stir the breadcrumbs into the browned butter. The browned butter adds a nutty richness to the topping.

5. Transfer the squash to a large mixing bowl. Add the potatoes and two-thirds of the oregano sauce. Toss until everything is well coated, ensuring each slice is kissed with the herby goodness.

6. Add the cheese and half of the breadcrumbs and toss again. This creates a lovely layer of flavor and texture throughout the gratin.

7. Taste one of the zucchini pieces and add more seasoning (salt or red pepper) if needed. This is your chance to adjust the flavors to your preference.

8. Transfer the squash to the lemon-zested pan, top with the remaining crumbs, and bake for somewhere between 40 and 50 minutes. This time will really depend on how thinly you sliced the squash and potatoes, and how much moisture was still in them.

9. You don’t want the zucchini to go to mush, but you need to be sure the potatoes are fully baked. Test the potatoes with the tip of a knife to ensure they are tender. If the breadcrumbs start to get a little dark, take a fork and rake them just a bit, that will uncover some of the blonder bits.

10. Remove from oven, and drizzle with the remaining oregano sauce. Let it rest for a few minutes before serving to allow the flavors to meld.

Expert Tips & Tricks

• For a deeper flavor, try grating a bit of Parmesan cheese into the breadcrumb mixture.
• Don’t skip the step of salting the squash. It really makes a difference in the final texture.
• If you don’t have fresh oregano, you can substitute dried, but use about half the amount.
• For easier slicing, use a mandoline for both the squash and potatoes. Just be careful with your fingers!
• If the top is browning too quickly, tent the gratin with foil during the last 15 minutes of baking.
• Feel free to use a mix of summer squash and zucchini for a more colorful dish.
• To add richness, consider including a very thin layer of crème fraîche or ricotta cheese between the squash layers.

Serving & Storage Suggestions

This Summer Squash Gratin is a wonderful side dish to grilled chicken, fish, or roasted vegetables. It also makes a satisfying vegetarian main course. Serve it warm, garnished with a sprig of fresh oregano or parsley.

Leftovers can be stored in an airtight container in the refrigerator for up to 3 days. To reheat, bake in a preheated oven at 350°F (175°C) until warmed through, about 15-20 minutes. You can also microwave it, but the breadcrumbs will lose some of their crispness. It is not recommended to freeze this gratin, as the texture of the squash and potatoes may suffer.

Nutritional Information

Nutrient	Amount per Serving	% Daily Value
Calories	365.8 kcal	N/A
Calories from Fat	218 kcal	N/A
Total Fat	24.3 g	37%
Saturated Fat	7.8 g	39%
Cholesterol	26.4 mg	8%
Sodium	455.4 mg	18%
Total Carbohydrate	30.2 g	10%
Dietary Fiber	3.9 g	15%
Sugars	4 g	N/A
Protein	8.6 g	17%

Note: Nutritional information is an estimate and may vary based on specific ingredients and portion sizes.

Variations & Substitutions

• Vegan: Substitute the butter with a plant-based butter alternative and use a vegan cheese substitute for the Gruyere. Nutritional yeast can also add a cheesy flavor.
• Gluten-Free: Use gluten-free breadcrumbs.
• Dairy-Free: Substitute the butter with olive oil and omit the Gruyere cheese. You can add a sprinkle of nutritional yeast for a cheesy flavor.
• Spicy: Add a pinch more red pepper flakes to the oregano sauce for an extra kick.
• Herby: Experiment with different herbs in the sauce, such as basil, thyme, or chives.
• Seasonal: In the fall, try using butternut squash or pumpkin in place of the summer squash.

FAQs (Frequently Asked Questions)

Q: Can I make this gratin ahead of time?
A: Yes, you can assemble the gratin up to a day in advance and store it in the refrigerator. Add the breadcrumb topping just before baking.

Q: Can I use pre-made breadcrumbs?
A: While fresh breadcrumbs are ideal for their texture, you can use pre-made breadcrumbs in a pinch. Look for whole wheat breadcrumbs for a more nutritious option.

Q: What can I use if I don’t have Gruyere cheese?
A: Fontina, Emmental, or even a sharp cheddar cheese are good substitutes for Gruyere.

Q: How do I prevent the gratin from being watery?
A: Salting the squash and draining it in a colander helps remove excess moisture. Also, don’t overcrowd the pan; if the squash is packed too tightly, it will steam instead of bake.

Q: Can I add other vegetables to this gratin?
A: Absolutely! Sliced onions, bell peppers, or mushrooms would be delicious additions.

Final Thoughts

This Summer Squash Gratin is a celebration of simple, fresh ingredients, transformed into a dish that’s both comforting and elegant. Whether you’re looking for a light and flavorful side dish or a satisfying vegetarian meal, this gratin is sure to please. Don’t be afraid to experiment with the ingredients and make it your own. I hope this recipe brings as much joy to your table as it has to mine. Bon appétit!