1. In a large pot, heat the olive oil over medium heat (skip this step for an oil-free version).
2. Add the chopped onion, carrots, and celery to the pot. Sauté for about 5 minutes until the vegetables begin to soften.
3. Stir in the minced garlic and spices (cumin, paprika, turmeric) and cook for another 1-2 minutes until fragrant.
4. Add the rinsed lentils, diced tomatoes (with their juice), and vegetable broth to the pot. Bring the mixture to a boil.
5. Once boiling, reduce the heat to low, cover, and let the soup simmer for about 20-25 minutes or until the lentils are tender.
6. Season the soup with salt and pepper to taste.
7. Serve the lentil soup hot, garnished with fresh parsley or cilantro if desired.

This lentil soup is high in protein and fiber, making it a great option for staying full during your fasting period. You can adjust the seasonings and add your favorite herbs or spices to suit your taste. As always, ensure that this recipe aligns with your specific fasting plan or dietary restrictions.