In a medium pot over medium heat, combine the potatoes and broth and simmer for 20 minutes or until potatoes are tender. While potatoes are cooking, prepare a skillet over medium heat. Wash leeks thoroughly and cut into ¼” disks, discarding the dark green portion of the leek. Sauté the leeks in butter for 10 minutes or until tender. Add the leeks and cream to the potatoes and stir well.