Start by making a soffritto, the Italian cousin of the mirepoix. Chop 1 cup of carrots, 1 cup of celery, 2 cups of onion, and about 5 or 6 cloves of garlic. Saute in olive oil until soft. Add 2 cups of lentils, 6 cups of chicken broth, 2 large bay leaves, a teaspoon of smoked Spanish paprika (pimentón ahumado), and some fresh black pepper. Bring to a boil, then reduce the heat and simmer for 30 minutes. If you use brown or green lentils, it may take longer. Stir in 1 tablespoon of Balsamic vinegar. You can puree the soup if you prefer it smoother, but I just serve it as is.
Serve garnished with croutons, fresh parsley and/or heavy cream, greek yogurt or sour cream.