Peel the turnips and cut them lengthwise into ‘chips’ about 2 cm thick. Heat the goose fat and oil in a casserole and brown the pieces of pork all over, a few at a time. Remove them to a plate, turn the heat down and fry the turnip chips in the same oil, together with the garlic cloves, turning them frequently over a gentle heat until they are lightly browned, after about 10 minutes. Add a pinch of sugar and cook a few minutes more.
Add the tomato sauce, celery, bay leaf, clove and chicken stock. Put back the pieces of pork and season well. Bring to a simmer and cook gently for 40 minutes, turning the pieces of pork from time to time. Sprinkle with chopped parsley before serving.