1. 1. Ask your butcher to debone the poultry while keeping the thighs and wings in order to give it back its shape once stuffed. Otherwise, do it yourself: cut the skin on the breast, then slide a good knife along the fillets until underneath, remove the rib cage to obtain the thighs, wings, and flattened breasts on each side.
2. 2. Preheat the oven to th.6-7/200°. Brown the chopped shallots and the mushrooms cut into pieces in a casserole dish with butter. Season with salt and pepper, add the chestnuts, the roughly chopped bread, the chopped coriander, mix well and let cool.
3. 3. Place the stuffing in the center of the capon, fold the sides to give it back its shape and place it in a bowl that will hold it while you sew the skin back together with a large needle and kitchen twine. Then cook the capon in the oven for 1 hour, then lower the thermostat to 5-6/160° and continue cooking for another 2 hours. Add water to the dish, then baste the poultry frequently during cooking.