Remove any damaged lentils and stones from the lentils.
Place the lentils into a colander and rinse well under cold running water to remove any dirt or other debris.
In a 6-quart or larger slow cooker, combine all the ingredients and stir well to combine. Cover and cook on LOW setting until the lentils and veggies are tender, about 8 hours.
Prior to serving, remove the thyme sprigs and bay leaf. Serve the soup hot, garnished with parsley and lime wedges.
Stovetop Instructions
In a large soup pot or Dutch oven, heat oil over medium-high heat. Add leek and sauté for 4-5 minutes. Add garlic and sauté until fragrant, about 1 minute.
Stir in lentils, carrots, broth, thyme and bay leaf. Cover and bring the mixture to a boil, once the mixture starts to bubble immediately reduce the heat and let simmer on low until soup is thick, for about 25-30 minutes.
Next, stir in the kale and cook, for 6-8 minutes more. Once the soup is done discard the thyme sprigs and bay leaf.
Taste and adjust the salt according to your taste. Serve the soup hot, garnished with parsley and lime wedges.
Notes
Cook time based on how long it takes to cook on your stovetop
Using the slow cooker, cook time is 6-8 hours.
For stovetop, use green or brown lentils. They tend to cook faster and you get a thicker consistency.