Unlike most lentils, red lentils cook quickly. This version, a take on the traditional Lebanese soup, is done in the slow cooker. After it's done cooking, it's punched up with a bit of vinegar, puréed, and garnished with onions, cilantro, and a spurt of fresh lemon.
When cooking, even in the slow cooker, be careful. You need to keep an eye on it because when the liquid gets too low it can burn. That's why this isn't a soup you want to jack up on high. It's also best to stay nearby, stirring every hour or so and adding stock as the soup starts to thicken. It's possible you'll need up to four additional cups of stock, so be sure to plan accordingly.
Finished with a bit of acid (red wine vinegar), the soup is puréed until smooth. If you prefer a chunkier texture, skip blending it entirely or use the pulse setting to keep some lentils intact.
When ready to serve, the soup is garnished with red onion, cilantro, and lemon juice.
Note: If you like your soup with a touch of creaminess, adding a dollop of plain yogurt works nicely.
- 1 tablespoon olive oil
- 1 large white or yellow onion, chopped (about 1 1/2 cups)
- 2 carrots, peeled and chopped (about 1 1/2 cups)
- 2 celery stalks, chopped (about 1 cup)
- 4 cloves garlic, minced (about 4 teaspoons)
- 2 teaspoons ground cumin
- 1/2 teaspoon cayenne pepper
- 1 1/2 teaspoons smoked paprika
- 4 cups dry red lentils, picked over for debris and rinsed
- 2 bay leaves
- 12 to 16 cups low-sodium vegetable stock or water
- Kosher salt
- 1 tablespoon red wine vinegar
- 1 large red onion, minced (about 1 cup)
- 1/3 cup minced fresh cilantro leaves
- 1 lemon, cut into wedges
Heat olive oil in a large sauté pan over medium heat. When oil is shimmering, add onion, carrots, and celery and cook, stirring periodically, until vegetables start to soften, about 5 minutes. Add garlic cook, stirring, until fragrant, about 1 minute. Stir in cumin, cayenne, and paprika, and continue cooking until fragrant.
Transfer mixture to a slow cooker. Add lentils, bay leaves and 12 cups of stock. Season with about 1 teaspoon of salt, stir to combine, and cover. Set slow cooker to low and cook for 4 hours, stirring hourly and adding in additional broth as needed to maintain a loose, soup-like consistency.
When the soup is done, discard bay leaves, transfer to a blender or food processor, and add vinegar. Adjust seasonings, if needed, and purée until smooth. Ladle into bowls and top with red onion and cilantro, and serve with lemon wedges.
Slow cooker, blender, or immersion blender