Heat the olive oil in a large pot over medium heat. Add the onion, carrots, celery, and garlic. Sauté for 5 minutes or until vegetables are tender. Add the cumin and oregano.
Add the lentils and vegetable broth. Bring to a boil, reduce heat, and simmer for 35-40 minutes or until the lentils are softened.
Add the spinach leaves, salt, and pepper. Simmer for another 5 minutes or until spinach is wilted and soup is heated through. Stir in hot sauce.
Taste and adjust seasonings as desired. Serve hot. Enjoy!
Notes
For a thicker soup, use less vegetable stock/broth or mash some of the lentils with a wooden spoon while they are cooking. If you want to add more protein, feel free to add in cooked diced chicken or sausage.