Lemony Black Lentil Soup with Crispy Kale and Yogurt

Prep: 15 mins

Cook: 30 mins

Difficulty: Easy

Servings: 6 Servings

This brothy bowl of lentils, warmly spiced with cumin and coriander and brightened up with lemon zest and juice, is the ultimate way to usher in soup season. Crispy kale chips lend salty crunch, a generous sprinkle of red pepper flakes adds heat, and a dollop of yogurt provides a creamy, cooling effect. It’s the most interesting thing to happen to lentil soup in a long time, so I implore you to head into the kitchen and ready that Dutch oven.

Ingredients

1 medium bunch curly kale (8 to 10 ounces)
1 medium yellow onion
4 cloves garlic
1 small lemon
2 cups dried black lentils (about 1 pound)
4 tablespoons olive oil, divided, plus more for serving
1 1/4 teaspoons kosher salt, divided, plus more as needed
1 teaspoon ground cumin
1/2 teaspoon ground coriander
1/4 teaspoon red pepper flakes, plus more for serving
6 cups low-sodium chicken or vegetable broth
1/2 cup whole or 2% plain Greek yogurt

Instructions

Arrange 2 racks to divide the oven into thirds and heat the oven to 300°F. Meanwhile, prepare the vegetables and cook the lentils.
Strip the leaves from 1 bunch curly kale and reserve the sturdy stems. For extra insurance, pat dry with paper towels — you want the kale to be as dry as possible in order for it to crisp. Tear the leaves into bite-sized pieces (6 to 7 packed cups) and divide between 2 rimmed baking sheets. Chop the stems into 1/4-inch pieces.
Dice 1 medium yellow onion. Mince 4 garlic cloves. Finely grate the zest of 1 small lemon. Juice the zested lemon into a small bowl.
Place 2 cups dried black lentils in a fine-mesh strainer. Pick through the lentils, discarding any broken or discolored ones. Rinse under cool water until the water runs clear, about 1 minute. Set aside to drain while you cook the vegetables.
Heat 3 tablespoons of the olive oil in a large pot or Dutch oven over medium heat until shimmering. Add the onion and kale stems and sauté until softened, 6 to 8 minutes. Add the garlic, 1 teaspoon of the kosher salt, 1 teaspoon ground cumin, 1/2 ground coriander, and 1/4 teaspoon red pepper flakes. Cook until fragrant, about 1 minute.
Add the lentils and 6 cups broth, stir to combine, and bring to a simmer. Cover and reduce the heat to maintain a gentle simmer. Cook, stirring occasionally until the lentils are tender, 25 to 30 minutes. Meanwhile, roast the kale leaves.
Drizzle the remaining 1 tablespoon olive oil and sprinkle the remaining 1/4 teaspoon kosher salt evenly over the kale leaves. Use your hands to massage it into the leaves to coat. Spread the kale into an even layer. Bake, stirring the kale and rotating the baking sheets between racks halfway through, until the kale is crisp, 18 to 20 minutes total.
When the soup is ready, remove from the heat. Stir in the lemon zest and half of the lemon juice. Add 1/2 cup Greek yogurt to the small bowl of remaining lemon juice, season with a pinch of kosher salt, and stir to combine.
Divide the soup among bowls. Top with the crispy kale, a dollop of lemon yogurt, a drizzle of olive oil, and more crushed red pepper flakes if desired.