Put the pheasant meat (not the backbone) in a large bowl, cover with the wine, 2 tablespoons of oil and the juniper berries. Cover with cling film and marinate in the fridge for six hours.
Drain through a colander, into a saucepan.
Boil the wine on medium heat for 2 minutes. Seal the pheasant meat in a very hot frying pan with the rest of the oil and reserve. Colour the lardons in the same pan and reserve.
In a cocotte, put the pheasant legs and thighs, backbone of the pheasants and wine marinade. Bring to the boil; skim if necessary; add the bouquet garni, garlic, carrots and onions. Cover with a lid, reduce the heat and simmer gently for 45 minutes. Add the pheasant breasts, lardons and mushrooms and simmer for another 10 minutes.
Strain the juices into a saucepan, discard the bouquet garni and backbone and cover the meat and vegetables with a damp cloth and keep warm.
Add the cold roux to the cooking juices, put over heat and whisk constantly until the sauce is thick enough to coat the back of a spoon (4-5 minutes).
Add the pheasant and vegetables back into the sauce and simmer for 3-4 minutes until hot through. Serve in a deep bowl or plated, scattered with the parsley and boiled potatoes and deep fried croutons (optional).