In a large saucepan, combine the chicken broth, carrots, leeks, and bay leaf. Bring to boiling; reduce heat. Simmer, covered, for 20 minutes. Add lemon juice, snipped thyme, savory (if you like), and pepper. Simmer, covered, for 5 minutes more or till carrots are tender. Cool slightly.
Remove bay leaf; discard. Place one-third of the carrot mixture in a food processor or blender. Cover and process or blend till smooth. Repeat with the remaining mixture. Return all to saucepan; heat.
To serve, ladle the soup into bowls. Top each serving with lemon slices and, if you like, lemon thyme or thyme. Makes 8 to 10 side-dish servings.
Halve this recipe to make 4 or 5 side-dish servings.