Last week, on a particularly freezing evening, I came home from working in the city to find that my mother-in-law had brought us dinner from one of our favorite local restaurants. Yay! She totally saved us, as I had literally nothing in the fridge except a carton of eggs and a head of broccoli. We wouldn’t have starved, but it wasn’t going to be a meal to write home about.
One of the things she brought over was crab bisque. It was incredibly delicious, but I could only manage a small cup. The bisque was so thick and rich that I felt like I was drinking heavy cream (which, let’s face it, I probably was). Still, it got me thinking about ways to make a thick, velvety, almost sinfully rich soup without any cream at all.
A good trick, I discovered, is to use a little bit of peanut butter. This soup is loosely based on a recipe from The New Book of Soups. I saw it in a local magazine at my hair salon, and it sounded so good that I actually took a picture of the page with my iPhone.
I planned to replace the heavy cream called for with full-fat coconut milk, but in the end I didn’t think it needed it. This soup tastes incredibly luscious–it’s hard to believe there are only four tablespoons of peanut butter in the whole pot. A big pinch of cinnamon stirred in at the end and a sprinkle of chopped peanuts are the perfect finishing touch.
I think this would be equally good with almond butter instead of peanut butter. For a little kick, add a pinch of red pepper flakes with the onion and leek. This recipe yields two quarts of soup, so you can enjoy one now and freeze one for later.
Sweet Potato Peanut Butter Soup
Makes about 2 quarts (8 cups)
Loosely adapted from The New Book of Soups
3 tablespoons extra virgin olive oil
1 medium onion, diced
2 leeks, halved lengthwise and thinly sliced (white and light green parts only)
1 clove garlic, minced
2 medium sweet potatoes, peeled and diced
Kosher salt and freshly ground black pepper
4 cups low-sodium vegetable broth
1/4 cup creamy peanut butter
1/4 teaspoon ground cinnamon
Chopped roasted salted peanuts, for serving
Heat the olive oil over in a large saucepan or Dutch oven over medium-high heat. Add the onion and leeks and sauté until softened, about 5 minutes. Add the garlic and sauté for 1 minute more. Add the sweet potatoes and season liberally with salt and pepper. Stir in the vegetable broth and bring to a boil. Reduce the heat, partially cover the pot, and simmer until the potatoes are tender, about 25 minutes.
Remove the pot from the heat and add the peanut butter and cinnamon. Puree the soup with an immersion blender. (Alternatively, puree the soup in batches in a regular blender.) Serve garnished with the chopped peanuts.