Place 40g/1 1/2 oz of the flour and seasoning in a large plastic bag and coat the chicken joints.

Heat the oil and 50g of the butter in a large flameproof casserole and sauté the onions and bacon until the onions have browned lightly. Add the mushrooms and fry for 2 minutes more. Remove with a slotted spoon and reserve.

Add the chicken pieces to the hot oil and cook  for about 5-6 minutes until browned. Add the brandy and, standing well back, light it with a match, then shake the casserole gently until the flames subside.

Add the wine, bouquet garni, garlic and sugar, and season. Bring to the boil, cover and simmer for 1 hour, stirring from time to time.

Add the onions, bacon and mushrooms, cover and cook for 30 minutes. Transfer the chicken, vegetables and bacon to a warmed dish.

Remove the bouquet garni; boil the liquid for 2 minutes. Cream the remaining butter and flour. Whisk in spoonful of the mixture to thicken the liquid.

Pour the sauce over the chicken and serve garnished with parsley and croutons.