Wash and chop the vegetables, including carrots, celery, onion, and garlic.

Heat olive oil in a large pot over medium heat. Add the diced onions and sauté until translucent, about 4-5 minutes, then stir in the minced garlic.

Mix in the chopped carrots and celery, cumin, thyme, and the bay leaf. Cook until the veggies soften slightly, about 3-4 minutes.

Pour in the vegetable broth and add the rinsed lentils; stir well and bring to a gentle boil.

Add the diced tomatoes and season with salt and pepper to taste. Reduce the heat to low and simmer uncovered for 30–35 minutes.

Before serving, taste the soup and adjust seasoning as desired. Serve hot with crusty bread or over rice.