After Thanksgiving, the big question is what to do with the leftovers. As someone who works on recipes each day, I have a different challenge: what to do with the leftover raw ingredients that I didn't end up using in any dishes at all.
This year it was a big bag of sweet potatoes still sitting on my counter after everything else was done. Personally, after a lot of holiday cooking, I'm in the mood for easy, soothing foods—big projects can wait a week or two while I catch my breath. Easy and soothing, for me, often means soup.
And so it was for those sweet potatoes. I started by using Kenji's low-temperature oven method to roast the sweet potatoes: sweet potatoes convert their starch to sugar best at gentle heat. Crank it too high and you'll halt their sweetening prematurely. Only after an hour at the low heat did I increase the oven temperature to help brown them a little and deepen their flavor.
While the potatoes cooked, I sweated onion, garlic, and carrot in a soup pot, then added the potatoes. I topped it off with some chicken stock (though homemade vegetable stock works just as well for those hoping to keep things vegetarian) and blended it to a smooth puree. A small splash of orange juice added some subtle extra flavor. The basic technique is outlined in this primer on creamy soups.
I decided to go above and beyond by passing my soup through a fine mesh strainer. It produces a significantly better texture, but I can't lie: it's a minor pain to do. Skip it or do it, as you prefer.
Then, for a garnish, I made a riff on gremolata by crushing pistachios, then stirring in orange zest (from the same orange I had juiced), scallions, mint, and olive oil.
Just like that, my problem was solved.