1. Heat olive oil in a large pot over medium heat. Add onion, garlic, carrots, and celery; sauté for 6 to 7 minutes until vegetables are softened.
2. Stir in tomato paste, paprika, curry powder, cumin, and red pepper flakes or chipotle peppers; cook for 1-2 minutes to deepen flavors.
3. Add lentils, black beans, vegetable broth, and bay leaves. Bring to a boil, then reduce heat to simmer, covered, for 25 to 35 minutes until lentils are tender.
4. Remove bay leaves. Partially blend the soup using an immersion blender, or transfer half of the soup to a blender and pulse to your desired consistency.
5. Stir in chopped kale and cook for an additional 1-2 minutes until wilted.
6. Finish with lemon juice, nutritional yeast if using, and adjust seasoning with salt and pepper to taste. Garnish with chopped parsley or cilantro before serving.