In a pan melt half the butter and fry the onions over a medium heat for 5 minutes. Add the mushrooms and fry for a further 3 minutes. Transfer with a slotted spoon to a casserole dish. Toss the meat in seasoned flour. Add the oil to the pan, increase the heat and brown the meat. Transfer the meat to the casserole dish. Deglaze the pan with half the Calvados to remove any bits stuck to the bottom. Add the cider and stirring continuously, bring to the boil. Place in the casserole dish. Top with sage and bay leaves. Cover and cook in a preheated oven 180?C, 350F, gas mark 4 for 1 3/4 hours or until tender. About 10 minutes before the end of the cooking time core the apples (but do not peel) and cut each into 4 rings. Melt the remaining butter in a large frying pan. Add the apples and toss in the butter. Sprinkle in the sugar and cook until the apples are a golden caramel colour but not mushy. Stir in the remaining Calvados and boil quickly to completely reduce the liquid. Remove the herbs from the casserole. Stir in the cr?me fra?che and chives. Serve alongside the apples, accompanied by rice and French beans. NOTES : Pork with apple is a classic combination, in this country and in France.