1. Heat oil in a Dutch oven over medium heat. Add onion to pan; cook 5 minutes or until tender, stirring occasionally. Add garlic and 2 teaspoons rosemary; cook 1 minute, stirring occasionally. Stir in potato and next 5 ingredients (through 2 cups water). Bring to a simmer; cook, covered, 20 minutes or until vegetables are tender.
2. Place 3 cups vegetable mixture in a blender. Remove center piece of blender lid (to allow steam to escape); secure blender lid on blender. Place a clean towel over opening in blender lid (to avoid splatters). Blend until smooth. Return to pan. Stir in cream, pepper, and salt.
3. Preheat broiler.
4. Arrange bread slices on a baking sheet. Sprinkle each bread slice with 1 tablespoon cheese; top evenly with remaining 1 teaspoon rosemary. Broil 1 minute or until cheese melts.