Summer Squash Gratin

I had to make this lovely summer gratin as soon as I saw a photo of it. So pretty and colorful! 🙂 It is a wonderful celebration of the bounty of summer squash.

We ate it as a vegetarian main dish with a crusty sourdough baguette. It would also be a fabulous side dish. This recipe was adapted from Food and Wine, contributed by Laura Rege. I used sweet cipollini onions from my CSA box in addition to the leeks.

After adding an additional sautéed CSA cipollini onion, I also made a mini-gratin with my leftover filling. 🙂 Great.

Yield: Serves 4 to 6 as a main dish (plus an additional mini-gratin, above, optional)

• 5 T extra-virgin olive oil, divided
• 2 small leeks, white and tender green parts thinly sliced into rounds
• 2 cipollini onions, halved and cut into slices (plus 1 additional onion if making a mini-gratin)
• 1/4 cup dry white wine (plus 1 additional T if making a mini-gratin)
• 3 medium zucchini, cut lengthwise into 1/8-inch-thick slices, preferably 
on a mandoline
• 3 medium yellow summer squash, cut lengthwise into 1/8-inch-thick slices, preferably on a mandoline
• coarse salt
• freshly ground black pepper
• 1 cup finely shredded Gruyère (about 2 ounces)
• 1 plum tomato, very thinly sliced crosswise
• flaky sea salt, for finishing
• crusty bread such as a sourdough baguette, for serving

1. Preheat the oven to 425°, preferably on convection.
2. In a large skillet, heat 1 tablespoon of oil over moderately high heat. Add the leeks, and onions, if using, and cook, stirring occasionally, until softened, about 3 minutes.
3. Add the wine and cook until evaporated, about 2 minutes.
4. Spread in a 9-inch round baking dish.
5. Using a mandolin, slice the squash lengthwise into 1/8-inch slices.
6. Meanwhile, on 4 large baking sheets, spread the zucchini 
and yellow squash and brush with the remaining 4 tablespoons of oil; season with salt and pepper.
7. Sprinkle with the cheese and let sit until slightly softened, about 5 minutes or up to 1 hour.
8. Tightly roll 1 piece of zucchini and set it on the leeks in the center of the dish.
9. Working 
outward from that center slice, continue rolling and coiling additional pieces of zucchini and yellow squash until you reach the edge of the baking dish.
10. Season the tomato slices with salt and pepper, then tuck in intervals between the zucchini and squash.
11. Scrape any cheese off of the baking sheets and sprinkle on top.
12. Place on a parchment paper-lined baking sheet, and bake for 30 to 35 minutes, 
until the zucchini and squash are tender and browned 
in spots. (I cooked mine for 33 minutes, and 27 minutes for the mini)
13. Remove from oven. While hot, sprinkle with sea salt.
14. Let cool slightly, then 
serve with crusty bread.

I’m sharing my summer gratin at Angie’s Fiesta Friday #180, co-hosted by Tracey @My Baja Kitchen and Jhuls @The Not So Creative Cook. Enjoy!

Note: If making the additional mini-gratin, saute the additional onion, adding 1 T wine cooking as directed above. Place in the bottom of a mini-pie dish and layer remaining squash and cheese. Cook as directed.

One Year Ago:

• Ottolenghi’s Tomato & Pomegranate Salad

Two Years Ago:

• Quick Zucchini Lasagna
• Roasted Zucchini Parmesan with Fresh Tomato Sauce

Three Years Ago:

• Silky Zucchini Soup
• 5-Minute Dips

Four Years Ago:

• Escalivada or Grilled Vegetable Salad with Parsley Vinaigrette
• Summer Vegetable & Nectarine “Ceviche”

About Josette@thebrookcook

I live in Stony Brook, New York on Long Island. I love garlic and baking. My hobby (and love) is to try new recipes. My favorite recipe resources include The New York Times, Food and Wine, Bon Appetit, and Martha Stewart Living. Enjoy!

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