Fill a medium saucepan with 2 inches of water and bring to a boil over medium heat. Place the potatoes into a steamer basket, cover and cook for 7 minutes.
Add the leeks on top of the potatoes, cover and cook for an additional 5 minutes or until the leeks are tender. Reserve steamer water. Let cool slightly.
Transfer the leeks and potato into a blender or food processor and puree on high for 1-2 minutes or until smooth and creamy, adding in reserved water in tablespoon increments if needed.