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As the vibrant hues of summer gently recede, and the air hints at the crispness of autumn, our culinary focus often shifts. Many are eager to savor the last of the season’s stone fruits, like succulent prune plums, or to indulge in the intense flavor of sun-ripened tomatoes before they vanish for the colder months. Others might already be looking ahead, envisioning comforting dishes centered around pumpkins and apples. Yet, for some, the essence of summer, particularly its abundant squash, remains a cherished desire.
This past summer presented a unique culinary journey for me, leaving me feeling as though I hadn’t quite had my fill of summer squash. So, on a recent Sunday visit to the local Schenectady farmers’ market, I seized the opportunity. With prices exceptionally low, I generously stocked up on zucchini and yellow squash, anticipating a week filled with delightful creations. Visions danced in my head: baking a tender zucchini bread, frying savory zucchini fritters with tzatziki, tossing summer squash spaghetti, and crafting light salads with shaved Pecorino. The possibilities seemed endless for these versatile vegetables.
However, my grand plans for a varied squash-filled week quickly narrowed. Tonight marks the third consecutive evening I’ll be preparing this particular gratin, and I still have enough squash on hand to extend this delicious trend through the weekend. This isn’t a complaint, but rather a testament to the sheer simplicity, adaptability, and undeniable appeal of this dish. It stands apart from many traditional gratins, which are often rich and heavy, laden with excessive cream and cheese. Instead, this recipe offers a lighter, more refreshing take, allowing the natural flavors of the vegetables to truly shine while still delivering that satisfying, comforting texture we crave.
The secret to its irresistible crunch and flavor lies in a modest yet impactful topping: a mere third of a cup of grated Parmigiano-Reggiano (or any hard cheese you have available) perfectly combined with a cup of freshly made breadcrumbs. This combination bakes into a golden-brown, crispy layer that provides a delightful textural contrast to the tender squash below. The foundation of this gratin is equally straightforward yet flavorful, comprising a layer of beautifully sautéed onions – or, as the original Bon Appetit recipe suggests, ripe tomatoes – crowned with thinly sliced summer squash. This thoughtful balance of ingredients creates a dish that is both wholesome and incredibly satisfying, proving that great flavor doesn’t always require an abundance of rich components.
What truly elevates this gratin is its incredible flexibility. While delicious in its basic form, it acts as a fantastic canvas for culinary creativity. You can effortlessly enhance its flavor profile by incorporating minced garlic, a medley of fresh herbs like thyme or oregano, or even a hint of savory anchovies for an umami boost. Once you’ve mastered the core recipe, you’ll find yourself naturally contemplating ways to adapt it for future seasons. Imagine the comforting possibilities this fall: perhaps a version featuring earthy sautéed kale, crisp green beans, or even a hearty layer of leftover cannellini beans. The beauty of this recipe lies in its forgiving nature and endless potential for variation, making it a staple you’ll return to again and again.
One of the most liberating aspects of this summer squash gratin is that it’s nearly impossible to mess up. There’s no need to fret over precise measurements or perfect layering techniques. Whether you prefer a thin, delicate layer of vegetables or a heartier, thicker foundation, the dish will turn out beautifully. Similarly, there’s no ideal ratio of squash to topping; feel free to adjust according to your preference for a cheesier, crispier crust or a more vegetable-forward experience. This is a truly rustic dish, embracing imperfection and celebrating wholesome, straightforward cooking. It’s incredibly fast to prepare, wonderfully easy to assemble, and consistently delicious. So, go wild! Experiment with different summer squash varieties – zucchini, yellow squash, or pattypan – and don’t hesitate to adjust the seasonings to your taste. Doesn’t summer squash deserve one last, glorious hurrah before we fully transition into the hearty flavors of autumn? Soon enough, we’ll be eagerly anticipating the arrival of crisp Paula Reds, sweet Ginger Golds, and juicy Jonamacs, but for now, let’s savor the golden goodness of this simple gratin.
This is an excellent opportunity to bring out your favorite mandoline for uniformly thin slices:
This simple summer squash gratin is more than just a side dish; it’s a versatile foundation for a wholesome and satisfying meal. For example, consider building a delicious “Meatless Monday” feast around it. Pair the warm, flavorful gratin with a generous serving of Suzanne Goin’s slow-cooked kale, enhanced with hearty white beans and a sprinkle of Pecorino cheese. Add a slice of rustic, crusty peasant bread for dipping and soaking up all the delicious juices. To complete this delightful spread, a small wedge of Drunken Goat cheese offers a sophisticated, tangy counterpoint that complements the earthy tones of the vegetables beautifully. This combination creates a meal that is not only nutritionally balanced but also rich in textures and flavors, proving that meatless meals can be utterly decadent and deeply satisfying. It’s an ideal way to celebrate the bounty of the garden while enjoying a comforting, home-cooked experience.
Finally, a little anecdote that warmed my heart last weekend: I stumbled upon this magnificent white Pyrex gem at a local flea market. Its dimensions are remarkably similar to the beloved Pyrex #322, but this particular find, a Pyrex #441, is absolutely perfect for baking a beautifully round little boule of bread. It’s been quite the challenge these past few days to resist the urge to dive into an eBay bidding war for another one of these vintage treasures. The joy of discovering such a functional and charming piece for my kitchen truly adds to the simple pleasures of cooking.
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Effortless Summer Squash & Onion Gratin
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Author: Alexandra Stafford at alexandracooks.com
Total Time: 40 minutes
Yield: 3–4 side servings 1x
Description
This light and incredibly easy summer squash gratin is a perfect way to celebrate late-season vegetables. Unlike many cream-laden gratins, this version focuses on tender, thinly sliced summer squash and flavorful caramelized onions, all topped with a delightful crispy breadcrumb and Parmesan crust. It’s a forgiving, rustic dish that’s quick to prepare and highly adaptable, making it an ideal side or a light vegetarian main. Adapted from a classic Bon Appetit recipe, it’s designed for simplicity and maximum flavor, allowing the natural sweetness of the squash and onions to shine through.
Ingredients
- 1 large onion, thinly sliced (about 2 cups once sliced)
- 4 Tbsp. high-quality olive oil, divided
- 1 cup fresh breadcrumbs (homemade are best for superior crunch)
- 1/3 cup grated Pecorino Romano or Parmigiano Reggiano (or any other firm, savory cheese like Gruyere or even a sharp cheddar)
- kosher salt and freshly ground black pepper, to taste
- 2 medium-sized summer squash (such as zucchini or yellow squash), thinly sliced (aim for 8oz (225g) to 12oz (340g) or roughly 2 to 3 cups once sliced with a mandoline or sharp knife)
- Optional additions for enhanced flavor: 1-2 cloves garlic, minced; a pinch of dried herbs like thyme or oregano; a touch of red pepper flakes for subtle heat.
Instructions
- **Prepare the Onion Base:** Heat 2 Tbsp. of the olive oil in a medium-sized ovenproof skillet (cast iron works wonderfully here) over medium heat. Add the thinly sliced onion. Cook, stirring occasionally, until the onions soften and begin to caramelize, a process that typically takes 10 to 15 minutes. For a deeper, sweeter flavor, allow the onions to caramelize slowly over lower heat for a longer period (up to 20-25 minutes), stirring regularly to prevent burning. If you’re short on time, simply sauté until they are tender and translucent. Season generously with kosher salt and freshly ground black pepper to taste. If using minced garlic or dried herbs, add them during the last 2-3 minutes of onion cooking.
- **Assemble the Topping:** While the onions are cooking, prepare the crispy topping. In a small bowl, combine the fresh breadcrumbs with the grated cheese (Pecorino or Parmigiano-Reggiano work best for a sharp, salty flavor). Drizzle in the remaining 2 Tbsp. of olive oil and toss gently to ensure the breadcrumbs are evenly coated. Season this mixture with a pinch of salt and pepper. The oil helps the breadcrumbs crisp up beautifully in the oven.
- **Layer and Bake:** Once the onions are ready, spread them evenly across the bottom of the skillet. Arrange the thinly sliced summer squash directly on top of the onions. You can create a single layer for a lighter gratin or stack them in two or three layers for a more substantial dish—remember, this gratin is forgiving! Finally, sprinkle the prepared breadcrumb and cheese mixture generously over the squash. Bake in a preheated oven at 350°F (175°C) until the squash is tender when pierced with a fork, and the breadcrumbs are beautifully golden brown and crispy, typically 20–25 minutes. *A note on oven temperatures:* I’ve found my oven thermometer to be a bit inconsistent. Both times I made this, the oven likely ran closer to 400°F (200°C) or even 450°F (230°C) for portions of the baking time. If you know your oven tends to run hot or cool, adjust accordingly. I suggest starting at 400°F (200°C) and checking the gratin after 15 minutes. If the topping is browning too quickly, reduce the oven temperature to 375°F (190°C) or 350°F (175°C); if it’s looking perfect, maintain the current temperature until done. The key is a tender squash interior and a glorious, crunchy crust.
- Prep Time: 10 minutes
- Cook Time: 30 minutes