WHY THIS RECIPE WORKS:
There’s a big dose of healthy, hearty greens in this deceptively delicious, silky-smooth soup. First, we built a flavorful foundation of sweet caramelized onions and earthy sautéed mushrooms. We added broth, water, and lots of leafy greens (we liked a mix of Swiss chard, kale, arugula, and parsley), and simmered the greens until tender before blending them until smooth. We were happy with the soup’s depth of flavor, but it was still watery and too thin. Many recipes we found used potatoes as a thickener, but they lent an overwhelmingly earthy flavor. Instead, we tried using Arborio rice. The rice’s high starch content thickened the soup to a velvety, lush consistency without clouding its bright, vegetal flavors. For a vibrant finish—and a touch of decadence—we whisked together heavy cream, sour cream, lemon zest, lemon juice, and tarragon and drizzled it over the top.
SERVES: 4 to 6
TOTAL TIME: 1 hour 30 minutes
INGREDIENTS:
- ¼ cup heavy cream
- 3 tablespoons sour cream
- ¼ teaspoon grated lemon zest plus ½ teaspoon juice
- ½ teaspoon minced fresh tarragon
- Salt and pepper
- 2 tablespoons extra-virgin olive oil
- 1 onion, halved and sliced thin
- ¾ teaspoon light brown sugar
- 3 ounces white mushrooms, trimmed and sliced thin
- 2 garlic cloves, minced
- Pinch cayenne pepper
- 3 cups water
- 3 cups vegetable broth
- ⅓ cup Arborio rice
- 12 ounces Swiss chard, stemmed and chopped
- 9 ounces kale, stemmed and chopped
- ¼ cup fresh parsley leaves
- 2 ounces (2 cups) baby arugula
INSTRUCTIONS:
- Prepare Lemon-Tarragon Cream: In a bowl, combine heavy cream, sour cream, lemon zest and juice, minced tarragon, and ¼ teaspoon salt. Cover and refrigerate until ready to serve.
- Brown Onion: Heat olive oil in a Dutch oven over medium-high heat. Add onion, brown sugar, and 1 teaspoon salt. Cook for about 5 minutes until the onion releases some moisture. Reduce heat to low and continue cooking, stirring often and scraping up any browned bits, until onion is deeply browned and slightly sticky, about 30 minutes. Adjust heat as needed.
- Add Mushrooms and Rice: Stir in mushrooms and cook until they release their moisture, about 5 minutes. Stir in garlic and cayenne and cook until fragrant, about 30 seconds. Stir in water, broth, and rice, scraping up any browned bits, and bring to a simmer. Reduce heat to low, cover, and cook for 15 minutes.
- Add Greens: Stir in chard, kale, and parsley, one handful at a time, until wilted. Return to simmer, cover, and cook until greens are tender, about 10 minutes.
- Add Arugula and Blend: Off heat, stir in arugula until wilted. Working in batches, process soup in blender until smooth, about 1 minute. Return soup to clean pot and bring to a brief simmer over medium-low heat.
- Serve: Season with salt and pepper to taste. Drizzle individual portions with lemon-tarragon cream before serving.
