Sauté the vegetables: In a large pot, heat the olive oil over medium heat. Add the diced onion, carrots, and celery. Sauté for 5-7 minutes, stirring occasionally, until the vegetables have softened and the onion is translucent.

1. Add garlic and spices: Add the minced garlic, cumin, turmeric (if using), thyme, and paprika to the pot. Stir for about 1 minute, allowing the spices to become fragrant.
2. Add the lentils, tomatoes, and broth: Stir in the rinsed lentils, diced tomatoes (with their juices), and vegetable broth. Bring the mixture to a boil.
3. Simmer the soup: Once the soup is boiling, reduce the heat to low and cover the pot. Simmer for 30-40 minutes, or until the lentils are tender. If needed, add more water or broth during the cooking process to maintain the desired consistency.
4. Add greens: If you’re using spinach or kale, stir it into the soup during the last 5 minutes of cooking. Let the greens wilt and soften.
5. Season and serve: Once the lentils are tender, taste the soup and adjust seasoning with salt, pepper, or more spices as needed. Stir in the lemon juice to brighten the flavors.
6. Garnish and serve: Ladle the soup into bowls and garnish with fresh chopped parsley. Serve with a side of crusty bread or a sprinkle of Parmesan cheese, if desired.