Clean the fish well. Chop together a slice of stale bread, one hard-boiled egg, two small onions, a few leaves of sorrel, a good piece of butter, salt and pepper. Mix this stuffing well and put it in the fish. Wrap it in oiled paper and cook in a moderate oven. The time of cooking depends on the size of the carp. It can also be cooked in butter and white wine, basting occasionally.