Melt the butter in a pan, add the garlic and cook over low heat for 1 minute. Add the milk, cream, potato, nutmeg, a pinch of salt and some black pepper. Bring to the boil and cook, covered, for 5 minutes. Add the carrot and cook for 3 minutes, then add the swede and cook for 3 minutes. Add the parsnip and cook for another 3 minutes, then finally add the turnip and cook