Rub the pork all over with the garlic and salt and pepper to taste, and set aside for 30 minutes.

Heat the oil in a flameproof casserole or large saucepan. Add the pork and fry until it is evenly browned. Add the onions and fry until they are soft. Pour over the wine and add the bouquets garnis. Bring to the boil, reduce the heat to low and cover the casserole. Simmer for 2 1/4 hours, or until the pork is cooked through and tender.

Transfer the pork to a warmed serving dish and keep hot. Bring the pan liquid to the boil, stirring constantly. Add the cornflour (cornstarch) mixture and cook, stirring constantly, for 2 minutes, or until the sauce thickens and is smooth.

Pour a little of the sauce over the pork and transfer the rest to a warmed sauceboat. Serve at once, with the meat.