This kale and spinach soup has a beautiful complexity. It's slightly sweet, with a bright note of lemon and the subtle aromatics of thyme, sage and garlic. Japanese yams are marvelously flavorful; they have a dark purplish skin and are snow-white inside. Ask for them at your farmers' market or grocery, but if they are unavailable, regular sweet potatoes can be substituted.

Anna Thomas
Source: EatingWell Magazine, Soup Cookbook




Ingredient Checklist


Instructions Checklist
  • Heat 2 tablespoons oil in a large skillet over high heat. Add onions and 1/4 teaspoon salt; cook, stirring frequently, until the onions are beginning to brown, about 5 minutes. Reduce the heat to low, stir in 2 tablespoons water, garlic and thyme and cover. Cook, stirring frequently until the pan cools down, and then occasionally, always covering the pan again, until the onions are greatly reduced and have a deep caramel color, 25 to 35 minutes.

  • Meanwhile, remove tough stems and ribs from kale and coarsely chop the greens. Peel yam (or sweet potato) and dice into 1-inch pieces. Coarsely chop spinach; set aside.

  • Combine the remaining 4 cups water and 3/4 teaspoon salt in a soup pot or Dutch oven; add the kale, yam (or sweet potato) and sage. Bring to a boil. Reduce heat to maintain a simmer, cover and cook for 15 minutes.

  • Stir in the spinach, return to a simmer, cover and cook, stirring once halfway through, for 10 minutes more. When the onions are caramelized, stir a little of the simmering liquid into them; add them to the soup. Add broth; return to a simmer, cover and cook for 5 minutes more.

  • Puree the soup in the pot with an immersion blender until perfectly smooth or in a regular blender in batches (return it to the pot). Stir in cayenne, a few grinds of pepper and 1 tablespoon lemon juice. If the soup is sweet to your taste, add more lemon juice; if it's too tart, add agave nectar, if desired. Just before serving, whisk the remaining 1 tablespoon oil into the hot soup. Garnish each bowl of soup with a drizzle of oil and 2 fried sage leaves.


Tip: To make fried sage leaves: Set a small strainer over a heatproof bowl. Heat about 1/2 inch olive or canola oil in a small saucepan over medium-high heat until shimmering but not smoking. Add sage leaves; fry just until crisp, 1 to 3 minutes. Drain in the strainer then spread out on a paper towel until ready to use.

To make ahead: Cover and refrigerate for up to 3 days.

Nutrition Facts

134 calories; protein 3g; carbohydrates 19g; dietary fiber 4.2g; sugars 5.3g; fat 5.6g; saturated fat 0.8g; vitamin a iu 14741IU; vitamin c 27.9mg; folate 99.3mcg; calcium 103.2mg; iron 2mg; magnesium 57.1mg; potassium 534.1mg; sodium 361mg; thiamin 0.1mg.

Reviews (6)

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9 Ratings
  • 5 star values: 4
  • 4 star values: 3
  • 3 star values: 1
  • 2 star values: 1
  • 1 star values: 0
Rating: 4 stars
Scary but good Because of the yams this green soup is kind of a scary color green but it tastes really good. The carmalized onions make this soup. I would suggest adding more cayenne. Pros: hearty full of flavor suprising Cons: needs more spice Read More
Rating: 3 stars
Good and healthy This is a good soup but I make it and eat it because it is so healthy and low in calorie. I will be making it again it's a nice start to a healthy week night dinner. I think it needs a little more spice (although I don't add the cayenne) I use an African Smoke spice that I bought a Trader Joe's and it makes everything smokey and delicious. Pros: Healthy Read More
Rating: 4 stars
Recommend I have made this soup a couple of times now. Definitely use the white Japanese sweet potatoes if you can find them they do make a difference. I like things spicy so added more cayenne. Did not make the sage leaves. I like it with a dollop of fresh goat cheese and some croutons. Pros: Healthy tasty Read More
Rating: 5 stars
Delicious This soup is really really good. I will be making it again. It would be great as a first course for a dinner party or just alongside a sandwich though it's not hearty enough to be a meal on it's own. Pros: Very tasty Read More
Rating: 5 stars
Wonderful combination of flavors. I have made this soup again and again. I omit the honey and use 2 cups less broth. Read More
Rating: 2 stars
Healthy but taste-wise only so-so I was out of thyme so substituted marjoram. Not sure that thyme would have made a significant difference in the overall taste. I prefer this as a cold soup but I doubt I will make this recipe again as the overall flavor and texture was not a big hit with either me or my husband. Pros: Healthy Cons: Not a flavor knock out Read More
Rating: 5 stars
Perfect blend of fall flavors I was a tiny bit apprehensive about making this soup due to the sheer amount of greens. I thought it might be "green overload" but it was delightful. The yams and caramelized onions totally balance out the bitter greens. I did make one slight change due to an ingredient shortage. I only had one sweet potato so I used one regular old russet potato along with one sweet potato. I'm not sure how much of a difference that made but either way it tasted great. Will definitely make again! Pros: Super healthy easy to make Cons: Time-consuming Read More
Rating: 4 stars
Satisfying and So Delicious The preparation is simple (omitted the fried sage) and the outcome is superb. Loved the flavor and texture along with the nutritional value. I'm making it again for the second time this month. Pros: Feel great about eating this healthy vibrant green soup for lunch dinner or a snack. Read More
Rating: 5 stars
A winner! I know this recipe was given as a great fall or winter soup but during summer I have been making BATCHES of this soup with the bountiful greens I have been getting. Don't feel the need to use only spinach or kale. I have used various lettuces and chard and even bok choy. So versitile and so delicious. Makes a great light summer soup that even my husband loves. (I have added small amount of wine to the onions before adding them to the pot and its yummy!) Read More