Joint the birds by separating the legs, thighs, and wings.
Remove the breasts, pull off the skin, and simmer carcasses and wings in 900ml water for 30 minutes to make stock.
Preheat the oven to 180°C and soak porcini mushrooms in 4 tablespoons of boiling water.
Heat oil in a frying pan and brown the guinea fowl pieces for 5 minutes.
Roast meat for 25 minutes, then remove breasts and roast legs for another 15 minutes.
Sauté lardons and shallots for 10 minutes, add thyme and sherry, then reduce liquid by a third.
Make a roux with butter and flour, then stir in 500ml of homemade stock until thickened.
Add the sauce to the lardons along with chopped porcini, their soaking liquid, and fresh mushrooms.
Cook for 5 minutes, season, stir in crème fraîche and parsley, and serve over the meat.