Bring 2 inches of water to a boil in a medium saucepan over medium heat. Place the potato into a steamer basket over the boiling water, cover and cook for 10 minutes.
Add in the zucchini on top of the potatoes, cover and cook for another 7 minutes or until potatoes and zucchini are tender. Do not over cook the potatoes. Reserve steamer water. Let cool slightly.
Place the zucchini and potato into a blender or food processor and puree for 1 minute or until completely smooth, adding the reserved steamer water into the puree in 1 tablespoon increments if needed.