Joint the rabbit and soak overnight in salted water, with vinegar, to cover. Drain and dry rabbit thoroughly, then coat with the flour. Heat oil and butter in a fireproof casserole or heavy saucepan, add onions, cut into quarters lengthwise, and cook for 3 minutes, then remove. Add rabbit and bacon and cook to a golden brown. Return onions. Pour in stock and wine, add salt, pepper, mustard and bouquet garni. Bring slowly to the boil and simmer, covered, for I1/2 hours or until rabbit is tender. If sauce is too thin, lift rabbit out of pan and boil liquid rapidly until slightly thickened. Add cream and chopped parsley. If necessary, add more seasoning to taste. Pour over rabbit and serve with new potatoes or creamy mashed potatoes.