Chop carrots, onion, and potato and put into a medium-size soup pot. Add rosemary, 1/4 teaspoon of salt, and enough water to cover the vegetables. Cover and boil until vegetables are soft.
Pull the veggies out with a slotted spoon and put into a food processor or blender. Discard the rosemary. Reserve the cooking liquid.
Puree the vegetables until smooth, and stir back into the water until well blended.
Season with the remaining salt and black pepper.
Bring mixture back to a simmer until cooked through. If the soup is too thick, add a little water until you get your desired consistency.
Serve immediately with fresh warm bread.