Ask your supplier to cut the cock into pieces. Keep the liver aside. Gently fry with butter in a casserole, not allowing to brown, add the finely chopped shallots, allow the shallots to mellow down. When starting to color sprinkle with the juniper brandy, cover, remove from the heat, leave to infuse for 5 minutes. Put over the fire again, moisten with the beer, until almost covering the meat and 4 tablesponns of cream. Bring to the boil then cook over a very low heat. After 30 minutes of cooking, add the finely sliced mushrooms. Twenty minutes before the end, add the liver kept aside. According to how tender the cock is, cook for 1 1/2 to 1 3/4 hours. To serve, arrange the pieces on the serving dish, keep warm, add 4 tablespoons of cream to the sauce again. If need be, reduce over a high heat while stirring. Remove from the heat and add 2 tablespoons of butter, whip the sauce to melt the butter which will thicken it. Pour onto the pieces of cock, sprinkle with chopped parsley. Serve with boiled potatoes.