Warm up on a chilly day with a bowl of hearty lentil soup. Red lentils can be found in Middle Eastern or gourmet markets. If unavailable, substitute the more common brown lentils.
Cook bacon in large saucepan or Dutch oven on medium heat until crisp. Remove all but 1 tablespoon drippings from pan. Add butter, onion, carrots, celery and garlic; cook and stir 5 minutes or until softened. Add beef stock and tomatoes; bring to boil.
Stir in lentils and seasonings. Return to boil. Reduce heat to medium-low; cover and simmer 30 to 40 minutes or until lentils are tender. Discard bay leaves.
With center part of cover removed to let steam escape, puree 2 cups of the soup in blender on high speed until smooth. Return pureed mixture to saucepan. Ladle into soup bowls.