Black Bean Soup with Sweet Potatoes

Heat the oil over medium heat in a 6-quart (or larger) Dutch oven. Add the onions and cook, stirring occasionally, until starting to soften and brown slightly, about 8 minutes. Add the garlic, coriander, cumin, aniseed, and 1/4 tsp. pepper and cook, stirring constantly, until fragrant, about 30 seconds. Add the broth, beans, sweet potatoes, and 3/4 tsp. salt and bring to a boil over high heat; skim any foam as necessary. Reduce the heat and simmer, uncovered, stirring occasionally, until the sweet potatoes are tender, about 15 minutes. Using a slotted spoon, set aside 3 cups of the beans and potatoes. Puree the remaining soup in batches in a blender. Return the solids to the soup and season to taste with salt and pepper. Serve topped with a dollop of the yogurt and a lime slice. You can store leftovers in the refrigerator for up to 5 days. nutrition information (per serving): Calories (kcal): 310; Fat (kcal): 6; Fat Calories (g): 50; Saturated Fat (g): 1; Protein (g): 17; Monounsaturated Fat (g): 2.5; Carbohydrates (g): 51; Polyunsaturated Fat (g): 2; Sodium (mg): 370; Cholesterol (mg): 0; Fiber (g): 11;