Heat olive oil in a large pot. Add carrot, celery, onion, and garlic and cook until tender.
Add lentils, sweet potato, broth, cumin, cinnamon, pepper, turmeric, coriander, and salt. Bring to a boil, then reduce to a simmer and cook until lentils are tender.
Add tomatoes and bring to a simmer again.
Add mustard greens in batches and cook until wilted.
All to simmer an additional 5-10 minutes, taste and adjust seasonings to your preference. It may require more salt depending on the amount of salt in your vegetable broth.
Recipe by For the Love of Gourmet at https://fortheloveofgourmet.com/moroccan-lentil-soup/