Carve the capon into several portions (legs each 2 breast, wings, parts)use the carcass to make the poultry stock.
Clarify 50g of butter. Sear the poultry pieces in a roasting pan on the skin side until golden brown. Turn the poultry pieces to the other side and brown them briefly, extinguish with a little cider and cook on a low temperature in the stove for 40 minutes, pouring the resulting juice or clear soup from time to time. Only then season with salt and season with pepper.
Cut the truffle into matchstick thin sticks. Simmer in a saucepan with 100 ml of cider for a few minutes. Drain the truffle pieces and collect the broth.
Remove the poultry from the roasting pan, skim off excess fat and sauté the finely chopped shallots for 3 minutes in the remaining fat and gravy. Extinguish with 200 ml of cider and add 100 ml of poultry stock, reduce the whole by 60%.
Add truffle stock and crème fraîche and thicken. Season with pepper and salt.
Mix in cold butter pieces (30 g). Cover the poultry pieces with the sauce. Sprinkle with the truffle sticks.