In a large pot over medium high heat, combine the oil, bacon, carrots, onions, and celery. Saute for 5 minutes, or until bacon is crisp. Stir in the flour until it's dissolved and mixture is pasty.
Slowly add the water, stirring constantly. Then add the bay leaves, salt, lentils, beef base, thyme, nutmeg, white pepper and potatoes. Stir all together well, bring just to a boil, reduce heat to low and simmer for 3 hours.