PLACE potatoes in large saucepan. Add broth; cover. Bring to boil on high heat; simmer on medium heat 15 min., stirring after 8 min. Uncover; stir potatoes. Simmer, uncovered, 5 to 6 min. or until potatoes are tender and most of broth is absorbed.
ADD Neufchatel. Reduce heat to low. Mash potatoes slightly until Neufchatel is melted. Add sour cream and Parmesan; mash until potatoes are smooth and heated through.