Begin by chopping the carrots, celery, and onion into small, even pieces. Mince the garlic and set it aside. Rinse the lentils under cold water and ensure there are no impurities.

In a large pot or Dutch oven, heat a drizzle of olive oil over medium heat for about 2 minutes until shimmering. Add the chopped onions and sauté until they become translucent, about 3-4 minutes. Then, stir in the minced garlic and cook for another minute until fragrant.

Next, toss in the chopped carrots and celery into the pot, stirring well to combine. Cook the mixture for about 5 minutes until the vegetables begin to soften.

Pour in the rinsed lentils, canned tomatoes, and vegetable broth, stirring continuously. Bring the soup to a gentle boil, then reduce the heat to low. Simmer uncovered for about 20 minutes.

After 20 minutes, check the lentils for tenderness; they should be soft but not mushy. Add spices like cumin and paprika, adjusting to taste. Stir in the fresh spinach, letting it wilt for about 2 minutes.

Once everything is cooked perfectly, ladle the soup into bowls. Garnish with fresh herbs, add a squeeze of lemon juice, and serve immediately with crusty bread.