Sweet Potato & Amaranth Soup

Kirstin, It's Not You, It's Brie

Sweet potatoes are the workhorse of my winter kitchen. Sweet, earthy and packed with more nutrients than a standard spud, they easily add a sultry thickness to many comfort foods. Here, toasted amaranth and browned butter provide a nuttiness, and ginger and sage make the dish even more inviting. I like this soup chunky and rustic, but if you’re a fan of smoother soups, run the cooked sweet potato-broth blend through the blender right before the recipe says to add the amaranth, then return it to the pot before adding the amaranth to cook for the last twenty minutes. Serve with a side salad.

Sweet Potato & Amaranth Soup
By Kirstin
Serves 4-6


2 pounds leek, untrimmed
2 tablespoons unsalted butter, plus 1 teaspoon for each soup bowl
pinch freshly ground nutmeg
1 medium sized carrot, medium-diced
salt and pepper to taste
4 garlic cloves, chopped
1 teaspoon fresh ginger, finely chopped
1 ¾ pounds sweet potato, large-diced
5 cups chicken stock
6 sprigs thyme
4 sprigs sage, plus 1 teaspoon chopped sage for each soup
1 cup amaranth (uncooked)
1 ½ teaspoon apple cider vinegar


Cut off and discard the top dark green part of the leek, about four or five inches from the bottom, and the roots. Slice the remaining leek lengthwise, then width-wise, half an inch thick. Wash well under running water to rid the leek of any debris.

Melt the butter in a soup pot on medium-hot heat. Add the leeks and nutmeg. Stirring occasionally, cook for about 10 minutes, or until the leeks are sweet and translucent. Season with salt and pepper. Add the carrot and garlic, lower heat to medium, and cook for 5 minutes. Add the sweet potato and stock and bring to a boil, then reduce to a simmer. Add the thyme and whole sage springs. Cover and cook for around twenty-five minutes, or until potatoes are tender enough to easily crush against the side of the pot with a spoon. Remove the herb sprigs and discard.

While potatoes are cooking, toast the amaranth in a sauté pan over medium heat until it turns a dark golden or light brown. After the sweet potatoes have cooked to the desired softness, add the amaranth to the soup pot, cover, and cook 10 minutes. Add vinegar and cook 5 minutes more. Use a potato masher to crush about three-quarters of the potatoes in the pot, then salt and pepper the soup to taste.

For the individual bowls:
Melt the desired amount of butter to top the portions in a medium-sized sauté pan and melt over medium heat. Scraping the bottom of the pan for about three to five minutes, cook until the butter turns light brown. Add the sage, stir for another minute, then drizzle over each soup bowl.

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9 thoughts on “Sweet Potato & Amaranth Soup

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  1. e.d. webb said:

    lovely recipes. Wondering where you find whole grain amaranth. and in another or your recipes: buckwheat. this looks as if it is delish! you have tantalized my taste buds.

    • Judith said:

      You can find Amaranth on food storage site like thrive life.com, Emergency essentials,or I bet even on Amazon.
      Very healthy and yummy.
      Recipe looks relish Emily.

  2. Lici said:

    When I will use the vinegar?

    • realbutter said:

      Hi Lici – The vinegar should be added in the last five minutes of cooking. Enjoy!

  3. Lici said:

    What else I can use for Leek?

    • realbutter said:

      HI Lici – Leeks have a unique flavor all their own and can be found at most grocery stores. In a pinch, you could substitute a very mild onion – even a green onion – or shallots. Enjoy the soup!

  4. Monidipa Chatterjee said:

    this is truly a keeper..thanks ton..yum yum!!!