Place the carrots, potatoes, parsnip, turnip, leek and onion into a large saucepan. Fill with enough water to cover. Bring to a boil and cook until the vegetables are tender. Drain off water and puree vegetables in a blender or using a stick blender.
Return the puree to the saucepan and stir in water to reach your desired thickness. Heat to a simmer and season with salt and pepper. Serve and enjoy.
