Why It Works
- Roasting the squash concentrates its flavor and deepens its natural sweetness.
- Finishing the purée with a small amount of cream and butter enhances the purée's texture and adds a sweet dairy richness that pairs well with the squash.
As a kid, I spent hours at the table every fall and winter helping cut up pieces of butternut squash for my granny's famous pies, made with her own homemade squash purée. (If using butternut squash purée in a pumpkin pie sounds strange, it shouldn't: it's the cucurbit most commonly used in canned "pumpkin" purée, as Stella has documented before.) Over the years she experimented with the best ways to tackle the squash. Boiling after it was cut up made for a smooth but tasteless and watery purée. Steaming was better, but left the purée stringy and pale—not good enough for a pie that needed to be smooth and full of flavor. Eventually I settled on roasting, which produced the best flavor, texture, and color, creating a sweet and complex purée with a beautifully burnt orange color, and velvety smooth body—this aligns with all of my own testing as well as all the work Serious Eats has devoted over the years to creating butternut squash purées for soups and pies.
Making a butternut squash purée is often just a stepping stone to some other preparation, like pies, a warming soup, ravioli, or even an add-in for your favorite pooch's pupcakes (Fido loves 'em!). But it's just as versatile as a side unto itself, to be served like so many vegetable purées alongside mains like grilled or braised meats. At its best, a butternut squash purée has a concentrated winter squash flavor with a well-developed caramel sweetness and earthy richness. It shouldn't be loose or watery, instead holding its shape well enough to not be confused with its soupy sibling.
In this recipe, we purée the squash in a food processor or blender until incredibly smooth and velvety, but you could just as easily make the purée by hand for a more rustic mashed texture.
As Daniel has written before when discussing the technique for his classic butternut squash soup, roasting works so well because it intensifies the squash's flavor by dehydrating the flesh while caramelizing its natural sugars. From there, you can build layers of flavor by beating in cream and/or butter, or a small amount of stock—infusing any of those liquids with woodsy herbs like sage or thyme will help play to the squash's autumnal vibes even more. Exactly how to go about all of this, though, matters. Below are some of the technical keys to butternut squash purée success.
How to Roast a Butternut Squash for Purées
Saying that it's best to roast butternut squash for purée is one thing, but explaining exactly how is another. Should you peel, seed, and dice the squash and then roast it? Or keep things simple by roasting large butternut halves? And is it better to roast those halves cut side up or down?
As always, you have options. Cutting the butternut into cubes is more work, but it has the advantage of creating more surface area for enhanced browning, leading to a purée with a sweeter and more deeply roasted flavor. That extra surface area also allows for more dehydration of the squash's natural water content, for a thicker purée that can absorb a higher amount of rich and flavorful liquids like cream or stock without immediately turning into soup.
Most of the time, though, simply halving the skin-on squash and scooping out the seeds is enough—just make sure to roast them cut side up on the baking sheet if you want to incorporate more liquid later. When cooked cut side down, moisture will be trapped in the squash, creating the wateriest purée and leaving you very little opportunity to add additional liquid when puréeing. That's fine if you're using the purée as a component in another dish, such as Stella does for the squash purée in her pumpkin pie, but it can be a problem if you want to serve it as a fully-formed side dish with a liquid like cream added.
As for oven temps, you want to go fairly high, in the range of 400 to 425°F, to promote browning and dehydration. Crank the oven higher, though, and the squash may develop a roasted crust that leans too dark and crispy, which could affect both the flavor and texture of the squash purée in undesirable ways.
How to Finish and Flavor Butternut Squash Purée
A basic butternut squash purée can be made of nothing more than the cooked squash plus some salt and the small amount of oil used for roasting. This will create a versatile purée that can then be used as an ingredient in other preparations, whether for a pie filling, a squash-flavored muffin or pancake batter, or a filling for ravioli. But with just a few small additions, you can make a purée so delicious it can act as a side dish all its own.
The main add-ins to consider are liquids like cream or stock, and fats like butter or olive oil. Each brings its own flavor, and the fattier options also act as texture enhancers. You can, of course, combine these. Cream and butter together are hard to beat—they both add richness and sweet dairy notes that pair well with the butternut's natural sweetness. Stock adds layers of flavor all its own, while its leanness can be offset with a finishing fat like butter or olive oil.
Beyond these choices, you can reach for other flavorings: woodsy herbs like sage, rosemary, and thyme can all be steeped in hot cream or stock or frizzled in melted butter before being strained out, infusing their flavor into every bite; the butter itself can be cooked until browned for a nuttier flavor; and there's hardly any end to the number of spices and seasoning that would work.
This recipe keeps things simple with just cream and butter, but feel free to customize the squash purée to your own tastes and needs.
Tips for Puréeing Butternut Squash
One of the trickier things about making a butternut squash purée is the actual puréeing part. Thick purées can refuse to form a proper vortex in a blender, making it difficult to fully purée all of the solids. If you have a blender that comes with a tamper (this is standard on Vitamix blenders), you can use it to push the chunks down towards the spinning blades without worry that you might accidentally touch them.
Otherwise, we recommend adding the liquid to the blender first, along with just a portion of the cooked squash and blending that before proceeding to add more squash; scraping and tamping in between blender pulses will still be necessary. You can also use a food processor, stand mixer, or immersion blender, all of which can make a purée in no time. Alternatively, as mentioned above, you can mash the squash by hand with a potato masher and/or beat it with a sturdy whisk for a chunkier, rustic texture.
- 1 large butternut squash (about 2 ¾ pounds; 1.25kg)
- Neutral oil, such as vegetable or canola, for coating the squash
- Kosher salt
- ¼ cup (60g) heavy cream
- 1 tablespoon (15g) unsalted butter
Adjust oven rack to middle position and preheat oven to 425°F (220°C). Using a chef's knife, cut the butternut squash in half lengthwise. Scoop out and discard seeds.
Set butternut squash halves, cut side up, on a rimmed baking sheet. Lightly coat the squash all over with oil, season all over with salt, and roast until well browned and a fork can easily slide through the flesh without resistance, about 1 hour. Remove from the oven and set aside until cool enough to handle.
Using a spoon, scoop out squash flesh; discard the skins. In a food processor or blender, combine the cream with about a third of the squash, then purée, stopping to scrape down sides as necessary, until smooth. Add remaining squash along with the butter and continue to purée, scraping and tamping as necessary, until very smooth. Season with salt, then serve warm.
Food processor or blender.
The squash purée can be refrigerated in an airtight container for up to 5 days. Reheat gently before serving.