Soften the onions in the oil in a heavy covered pan. After 10 minutes add the garlic cloves, then the peeled and sliced parsnips, reserving any which have already been roasted to add later (). Cook all the vegetables together for 10 to 15 minutes until they are soft, stirring them occasionally and adding any pre-roasted parsnips a few minutes before the end. Strain the hot stock into the vegetable mixture, add the salt and some freshly ground black pepper, simmer for 15 to 20 minutes, then liquidize. Taste for seasoning and add the juice of the freshly squeezed orange. () Parsnips give of their full sweetness only when roasted and can taste overbearingly rank when cooked in other ways.