Otherwise Trash: Whole Squash Soup

For years, I struggled to make a winter squash soup I wanted to eat on repeat, until now. Meet my Whole Squash Soup. This no-waste soup is made with a seed-and-pulp-thickening broth that adds flavor and creaminess. For it to work, you need squash with large cavities that contain many seeds and lots of pulp. Look beyond butternut, honeynut, and acorn. Choose the larger, round squashes—Carnival, Blue Hubbard, Kabocha. If you can, grab one with skin thin enough to eat (once roasted).  You’ll puree the flesh and skin at the end.

This soup is made in parts, simultaneously--the roasted squash and the squash broth.  Splitting techniques not only saves you time, but roasting the squash deepens it’s flavor. I suggest roasting the whole squash, no matter its size, so even if you don’t use it all for the soup—that’s a call you’ll make when you blend the squash and stock at the end—you can have leftovers to enjoy on their own.

Yield 4 servings

1 Carnival or other squash (about 3 pounds) with thin skin, washed well, then cut in half through the stem, seeds and pulp removed and reserved
8 tablespoons butter, divided
5 tablespoons honey
1 teaspoon ground mustard
1 teaspoon ground cumin
1 teaspoon ground allspice
1/2 teaspoon coarse kosher salt
2 thin leeks, white part sliced (about 1 cup)
4 cups excellent chicken or vegetable stock

Preheat oven to 425 degrees F.

Cut the cleaned, seeded, and scraped squash into 1-inch wedges.  Place them in a baking dish. In a small pan or pot, melt 4 tablespoons of the butter.  Add the honey, spices, and salt and bring to a near simmer to combine and infuse, then pour this mixture over the squash pieces.  Lay the pieces on one flat side and place in the oven.  Roast for 15 minutes, then flip the pieces over.  Roast until they are knife-tender, another 15 – 20 minutes.  Remove from the oven to rest.

Meanwhile, melt the remaining 4 tablespoons of butter in a large pot over medium-high heat.  Add the leeks and squash seeds and pulp.  Cook, stirring frequently, until the butter has been absorbed, the leeks are completely soft, and the pulp begins to stick to the bottom of the pan and brown, about 20 minutes.  Do not let the squash pulp burn.  Add the stock and scrape the bottom of the pan with a wooden spoon or spatula to release the brown bits into the broth.

Transfer the contents of the pot to a blender and puree until very smooth.  Pour the stock through a fine mesh strainer back into the pot, discarding any unblended seeds.  You should have about 4 cups of creamy, flavorful stock.

Once the squash wedges are roasted, puree them with the strained stock, starting with just half of the pieces, and making sure to include all of the sweet and spiced juices in the pan.  If the squash skin is thin enough, you will not have to strain the soup at this point, but taste and decide for yourself.  At this point, you’ll also want to taste and adjust the salt and spices as needed. 

Serve the soup hot or cold. In the photo above, it’s served with a huge dollop of herb sauce.