Step Aside, Butternut Squash—This Winter Squash Is Our Latest Love

Pair wedges of roasted acorn squash with thick slices of jammy, caramelized red onions, then top it with an orange juice- and honey-tinged vinaigrette for a delicious side. The key to its success is our unique roasting technique.

Step Aside, Butternut Squash—This Winter Squash Is Our Latest Love
Overhead view of rowasted squash
Serious Eats / Amanda Suarez

Come fall and winter, well after juicy tomatoes have faded from market stands, winter squashes step into the spotlight to become a star ingredient in many kitchens. Although butternut squash gets more attention, acorn squash really deserves a place on your dinnertime roster—with its edible green exterior and nutty, sweet orange flesh, it's beautiful on the plate and pairs wonderfully with plenty of other vegetables. It's also mild enough to serve as an almost-blank canvas for a wide range of flavors, such as the sweet and tangy date-orange dressing it's paired with in the recipe we're sharing here from our Birmingham, Alabama-based test kitchen colleague Elizabeth Mervosh

For this autumnal side, wedges of the sweet, creamy squash are paired with thick slices of jammy, caramelized roasted red onion, then drizzled with an orange juice– and honey-tinged vinaigrette that’s studded with dates, and finished with crunchy pistachios. The playful combination of fall flavors is not only delicious, but sure to be the most talked about dish at your next holiday gathering. (Sorry, mashed potatoes!)

Closeup of roasted squash
Serious Eats / Amanda Suarez

In developing this recipe, it was important for us that the roasted acorn squash and onions have a tender and moist interior and sweet caramelization on the exterior—we didn't want any dry and burnt or soggy, undercooked, and tough squash and onions. To achieve the ideal texture on both vegetables, Elizabeth roasted batch after batch of acorn squash and onions and came up with this clever roasting method that ensures tender, perfectly browned vegetables every time.

Key Techniques for Perfectly Roasted Acorn Squash With Onions

Cut the vegetables to an even thickness. Cutting the squash and the onions into similarly-sized wedges not only ensures an attractive presentation, but it also promotes even cooking. We found it easier to cut the squash crosswise (against the ridges of the squash) rather than along the ridges, which—bonus!—also shows off the squash's attractive fluted sides. And don’t bother attempting to peel the squash; its natural ridges make that almost impossible. Just roast it with the skin on—it's typically thin enough to eat, but if you prefer it without the skin, the meat of the squash will peel away easily from the skin once the squash is roasted.

Roast the onions and squash on separate baking sheets. Elizabeth realized early on in her testing that the onions and squash cooked at different rates. Cooking them together was a recipe for undercooked crunchy onions with tender squash, or perfectly cooked onions with mushy overcooked squash. The solution? Roasting them on separate sheet trays, which ensures the squash is tender and the onions soften evenly.

Arrange vegetables along the perimeter of the sheet pan for even roasting. Roasting on separate sheet trays still wasn’t enough to guarantee evenly browned and properly cooked vegetables. When the vegetables were just randomly scattered over the trays, they browned OK, but the browning wasn’t consistent: The slices on the edges of the pan were over-browning, while the slices in the center of the sheet were still pale. By arranging the squash and onion slices evenly around the perimeter of the baking sheet and avoiding the middle of the pan altogether, then rotating the sheet halfway through roasting, all of the slices browned well. 

Arranging squash
Serious Eats / Amanda Suarez

Start by steaming the onions. A common problem with roasting onions is that their outer layers can dry out and turn leathery before the interior petals are tender and the bottoms well browned. We wanted roasted onions that were soft and juicy from top to bottom. To get around this problem, we started by covering the pan of onions tightly with aluminum foil, roasting them briefly—just 10 minutes—then uncovering them and letting them finish roasting while the squash cooks on the bottom rack. Covering the onions traps in their steam, and that steam is a powerful cooking medium that softens the onion’s outer layers, ensuring that the exterior peels won’t dry out.

Jumpstart the squash’s browning by preheating the baking sheet. While placing the squash around the perimeter of the sheet tray ensures even cooking, our testing showed that even when we cranked the heat up and baked the squash on the lowest oven rack (closest to the heat source), the bottom cut sides of the squash were still not getting as browned as we wanted them. The solution was fairly simple: Preheating the baking sheet before quickly arranging the squash on the hot sheet to roast, which helped greatly with browning. Once the squash hits the pan, it starts searing immediately.

Once your vegetables are roasted, all that’s left is to whisk together a punchy vinaigrette that’s enhanced with sweet orange juice, honey, and dates with a hint of heat from chile powder. Then this fall side is ready for its close-up.

Adjust oven racks to middle and lowest positions. Place a large rimmed baking sheet on the lowest oven rack. Preheat oven with baking sheet to 475°F (245℃). Line a second large rimmed baking sheet with aluminum foil. Cut each onion half through the root end into 4 (about 1 1/2–inch-thick) wedges. Brush onion wedges all over with 1 tablespoon oil. Arrange wedges, cut side down and evenly spaced, along outer edges of prepared foil-lined baking sheet. Cover baking sheet tightly with aluminum foil. Roast on middle rack for 10 minutes. 

Brushing onions with oil
Serious Eats / Amanda Suarez

While onions are roasting, cut each squash half crosswise into four 1 1/2– to 2-inch-thick half-moon wedges; transfer to a large plate. Using a pastry brush, brush squash wedges with 2 tablespoons oil, and sprinkle evenly with 1 teaspoon salt, and 1/2 teaspoon pepper.

Two image collage of cutting squash and brushing with oil
Serious Eats / Amanda Suarez

After onions have roasted for 10 minutes, carefully remove the empty preheated baking sheet from oven. Working quickly, arrange squash wedges on the preheated baking sheet, cut side down and evenly spaced, along outer edges of baking sheet (spoon the squash pieces into each other to maximize space). Roast on lowest oven rack. Let onions and squash roast until onions are softened and translucent, 10 minutes longer.

Arranging squash
Serious Eats / Amanda Suarez

Remove onions from oven and carefully remove foil. Brush with 2 tablespoons oil and sprinkle with 1 teaspoon of the salt and remaining 1/4 teaspoon pepper. Return to middle oven rack and continue to roast both onions and squash, uncovered and flipping squash once halfway through, until bottom sides of onion wedges are lightly browned and squash are browned, about 20 additional minutes.

Brushing roasted onions with oil
Serious Eats / Amanda Suarez

While vegetables roast, place dates, orange juice, vinegar, honey, pinch of chile powder, and remaining 3 tablespoons oil, and 1/2 teaspoon salt in a small bowl. Stir and mash dates using the back of a spoon until mixture is thickened and creamy but still loose enough to drizzle. 

making date mixture
Serious Eats / Amanda Suarez

Transfer roasted squash and onion wedges to a large serving platter. Drizzle with date-orange dressing and garnish with pistachios. Serve.

Finished squash and onions
Serious Eats / Amanda Suarez

Special Equipment

Pastry brush, 2 rimmed baking sheets

Notes

You can use hot honey in place of the regular honey. If using hot honey, omit the pinch of chile powder. 

Make-Ahead and Storage

The dressing can be made ahead and refrigerated for up to 3 days. Bring to room temperature and whisk to recombine,thinning with a teaspoon of water if necessary.

Leftover roasted vegetables and be refrigerated in an airtight container for up to 5 days. Serve at room temperature or reheat in oven.