![Butternut Squash Casserole with Leeks, Prosciutto, and Thyme](https://cdn.statically.io/img/www.foodandwine.com/thmb/sKMSBLHBubn4esPdQrVbM_0unGg=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/butternut-squash-casserole-with-leeks-prosciutto-and-thyme-FT-RECIPE0924-fa4d868b8be94acbb4a624d975678f67.jpeg)
Food & Wine / Photo by Brie Goldman / Food Styling by Lauren McAnelly / Prop Styling by Sue Mitchell
This luscious butternut squash casserole is the ideal accompaniment to roasted meats and birds but is hearty enough to be cut into large squares and served as a brunch dish or main course with a green salad on the side. Start by roasting the squash with olive oil, thyme, salt, and pepper until it begins to caramelize and become tender. While the squash roasts, sauté the leeks until they too are tender. The vegetables are then tossed with a savory custard, bread, and prosciutto, then baked in a casserole dish for a luxurious fall side dish.
Frequently asked questions
What are the best ways to eat butternut squash?
We can’t possibly count the number of ways we love to cook and consume butternut squash but let’s give it a try. Butternut squash soup is a simple but delicious fall recipe that you can eat for lunch or as a light starter for dinner. Top it with crisp pancetta or bacon and crème fraîche for a luxurious upgrade. Slice or dice it and roast it as a bright vegetable side dish. Or mash it with butter, cream, a splash of orange juice, and ground cinnamon for a light and bright side dish.
Should you wash butternut squash before cooking?
Even though most butternut squash recipes call for peeling and discarding the skin, you should still thoroughly wash it under warm water until it’s clean of dirt. Pat the squash dry with a paper towel before continuing with the recipe.
Notes from the Food & Wine Test Kitchen
Be sure to thoroughly wash the leeks before slicing them. They are prone to trapping lots of dirt and sand between their thin layers, so be sure to rinse it all out before cooking with them. You can also soak the leeks in water for 20 minutes before prepping, which will help to release anything that’s trapped between them.
Once baked, it’s important to let this butternut squash casserole sit for at least 15 minutes before serving. This will allow the custard to set, making it easier to serve clean, even portions.
Ingredients
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3 pounds butternut squash, peeled, seeded, and cut into 1/2-inch dice
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2 tablespoons extra-virgin olive oil
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2 tablespoons finely chopped thyme leaves
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Kosher salt
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Freshly ground black pepper
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1 tablespoon unsalted butter
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3 leeks, white and light green parts only, halved lengthwise and thinly sliced crosswise (about 4 cups)
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6 large eggs
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2 1/2 cups half-and-half
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1/4 cup freshly grated Parmigiano-Reggiano cheese
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8 ounces baguette, crusts removed and bread cut into 1/2-inch dice
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4 ounces thinly sliced prosciutto, cut into thin strips
Directions
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Preheat the oven to 400°F and butter a 9- x 13-inch baking ceramic baking dish. In a large bowl, toss the butternut squash with 1 tablespoon of the olive oil and the thyme. Season with salt and pepper. Spread the squash on a baking sheet in a single layer and roast for about 25 minutes, until tender, tossing once halfway through. Let cool.
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Meanwhile, in a medium skillet, melt the butter in the remaining 1 tablespoon of olive oil. Add the leeks and season with salt and pepper. Cook over moderate heat, stirring, until tender, about 20 minutes. Let cool slightly.
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In a large bowl, beat the eggs with the half-and-half, cheese, 1 teaspoon of salt and a 1/2 teaspoon of pepper. Stir in the bread and let stand for 10 minutes. Fold in the squash, prosciutto and the cooled leeks. Transfer the mixture to the prepared baking dish and bake for about 1 hour, until lightly golden on top. Let stand for 15 minutes before serving.