The idea of sweet potato and peanut soup came to me in the middle of the night. Really. All I know is that I woke up one morning with the idea of making a soup with those two ingredients. I had no idea about what other things might be in the soup to add flavor, but, I did know enough that I must have seen or read a recipe that sat in my brain until that morning. I searched the Scratchin’ Central library to no avail, so it was off to search the Internet.
As expected, a quick search showed dozens of sweet potato and peanut soups; we decide to use this African Sweet Potato and Peanut Soup recipe as our starting point.
Just a couple of things to note. Harissa is a very spicy paste from North Africa made from dried chilies, garlic, and other spices. It’s easy to make, stores well, and adds a blast of heat to anything. Having learned about it, we try to keep a small jar on hand at all times. For the vegetable stock, we always make our own: simply save vegetable trimmings through the week, then simmer them in water for 45 minutes. Strain and you have vegetable broth. Finally, peanut butter. We use peanut butter made from peanuts. Nothing else. No corn syrup solids, no sugar, no salt. After all, it’s peanut butter, not corn syrup butter. To get this just-peanuts peanut butter, we buy Trader Joe’s unsalted, organic version. Finally, for the onions, we used some of those caramelized onions that we froze earlier this year.
Procedure in detail:
Cook onions. Heat the oil in a large saucepan over medium heat. When hot, add the onions and cook, stirring occasionally, until they begin to brown, about 10 minutes or so. We started with some previously frozen, caramelized onions, so we only had to let them thaw in the pan. If you want to speed up the browning, sprinkle just a bit of salt over the onions (to draw out moisture) while they cook.
Toast and grind spices. Since we used whole spices, we decided to toast them before grinding. If you’re using only dried spices, you can skip this step, or, you can toast the ground spices; just watch closely to make sure they don’t burn. The toasting does two things, first, it’ll make the seeds easier to grind as they’ll become brittle, but, more importantly, it’ll add a depth of flavor to the spices and eliminate the raw taste. So, place the cumin, coriander, and clove in a small skillet over medium heat and toast, shaking or stirring often, until fragrant, about 5 minutes (less for ground spices). Transfer to a spice grinder or mortar and pestle and grind.
Add garlic and spices. Once the onions are lightly browned, add the garlic, ginger, cumin, coriander, cloves, and cinnamon. Stir everything around and cook for about 2 minutes, stirring all the while. You should have something like a spice onion paste.
Add vegetables. Add the sweet potatoes, carrots, and tomato and stir to coat. Continue cooking for about 5 minutes, stirring occasionally, or until the tomato just begins to break down.
Add broth. Pour in the broth, add a teaspoon of kosher salt, and increase the heat to high. Bring the soup to a boil, then reduce to a simmer, and cook, covered, until the vegetables are soft, about 30 to 35 minutes.
Blend. Working in batches, if necessary, transfer the soup to a blender and process on the highest speed until very smooth. Remember to use care when blending hot liquids and vent the lid slightly to let the expanding air escape. If you don’t do so, the lid can pop off, sending scalding soup everywhere. Once the saucepan is empty, quickly wash it out so you can pour the soup back into it.
Strain. Since we used a variety of whole spices and we want a very smooth soup, that means strain the soup. It takes only a couple of minutes and makes for a nicer soup, so why no? Set up a strainer and pour the soup through it.
Add cayenne and peanut butter. Add a pinch of cayenne — we used about 1/8 of a teaspoon, which matches our tolerance for spice levels. You can use more or less, according to what you like. Add the peanut butter and stir in until melted and smooth.
Adjust. Taste and add salt if needed.
Serve. Ladle into bowls, and top with a dollop of harissa, if desired. Or, if there are people who don’t want the additional spice, just bring the harissa to the table as a condiment.
This soup was great! It tasted of peanuts, but not just peanuts; instead, it was complex, rich, and flavorful, tasting of the various spices, and sweet potatoes, along with the peanuts. The peanut butter made for a creamy, smooth soup, reminiscent of standard cream soups, but tasting far more exotic. We easily ate all four servings for our dinner, which we think makes the soup deserve four stars.