Many squash soups do not live up to their potential. Rather than being lustrous, slightly creamy, and intensely “squashy” in flavor, they are vegetal or porridge-like, and sometimes taste more like a squash pie than a squash soup.
Knowing that my basic method would be to cook the squash and then puree it with a liquid, my test focused on how to cook the squash for the soup. Some recipes suggest boiling the squash in a cooking liquid, others roasting it in the oven, others sautéing it on the stove-top.
I tried boiling the squash, but having to peel the tough skin away before dicing it seemed unnecessarily tedious. I eliminated the sauté technique for the same reason. While the roasting was infinitely more simple than my attempts at boiling or sautéing (all I had to do was slice the squash in half, scoop out the seeds, and roast it on a rimmed baking sheet), it produced a caramel-flavored soup with a gritty texture. Roasting also took at least one hour – too long for what should be a quick, no-nonsense soup.
In an effort to conserve time without sacrificing the quick preparation I liked from the roasting test, I decided to try steaming the squash. In a large Dutch oven, I sautéed shallots in butter (I tried garlic and onion but found them too overpowering and acrid with the sweet squash), then added water to the sautéed shallots and brought the mix to a simmer. I seeded and quartered the squash and placed it into a collapsible steaming insert, then added the squash and insert to the Dutch oven. I covered the pan and let the squash steam for 30 minutes until it was tender enough to show no resistance to a long-pronged fork. This method proved to be successful. I liked it because all of the cooking took place in just one pot and, as a bonus, I ended up with a squash-infused cooking liquid that I could use as liquid for the soup.
But there was a downside. Essentially, steaming had the opposite effect of roasting: whereas roasting concentrated the sugars and eliminated the liquid in the squash (which is what made the roasted squash soup gritty), steaming added liquid to the squash and diluted its flavor.
As I was preparing squash one morning, it occurred to me that I was throwing away the answer to more squash flavor – the seeds and fibers. Instead of trashing the scooped-out remnants, I added them to the sautéed shallots and butter. In a matter of minutes, the room became fragrant with an earthy, sweet squash aroma, and the butter in my Dutch oven turned a brilliant shade of saffron. I added the water to the pan and proceeded with the steaming preparation. After the squash was cooked through, I strained the liquid of seeds, fibers, and spend shallot, then blended the soup.
To intensify the sweetness of the squash (but not make the soup sweet), I added a teaspoon of dark brown sugar to the blender jar. Not only was this batch of squash soup brighter in flavor, but it was more intense in color as well. To round out the flavor and introduce some richness to the soup I added 1/2 cup of heavy cream. Now the soup was thick, rich, and redolent with pure squash flavor.
As is true with many creamed soups, texture is almost as important as flavor. I found blending the squash in batches with just enough liquid to make a thick puree worked best – the thicker base provided more friction and made it easier for the blender to smooth out any lumps or remaining squash fibers. Once all the squash was pureed to a silken texture, I added the remaining liquid and cream and briefly pulsed the soup to combine. I heated the soup briefly over a low flame and stirred in a little freshly grated nutmeg. In under one hour and with only one pot, I made a squash soup that offered nothing less than autumn in a bowl.
For a traditional butternut squash soup recipe, and a few tasty variations, please click HERE