Swans (at least in the UK, and maybe in NZ as well) are the property of the crown, and eating them is restricted to some of the ancient livery companies, some of the Oxford and Cambridge colleges, and some others.
As the (non-PC) limerick has it: There once was a student of St Johns Who attempted to **** the swans When up spoke a porter Saying 'Please take my daughter, Them birds is reserved for the dons!
That said Swan (as ceremonially served at St Johns Cambridge) is like tough, fishy duck. The only way to deal with it is as a ballotine or galantine. That is carefully pluck the swan, preserving its feathers (cut the wings and neck off whole before plucking).Cut round the vent and remove the guts. Reserve the liver, make stock from the heart and gizzard, and discard the rest. Bone/skin it from the neck end, without breaking the skin. Stuff the skin with a good forcemeat, well truffled, and with any of the meat you have cut off the carcass minced finely, and moistened with some brandy. Add the carcass to the stock. Some add pistachio nut kernels and quails eggs, or stuff the swan with a boned duck, (stuffed with a boned pheasant, stuffed with a boned quail, stuffed with an egg, stuffed with an olive - stuffed of course with anchovy..If you are making this, the trick is to put in lots of eggs stuffed with olives so that everyone thinks they have a slice thru the centre..). Tie the swam up carefully in muslin and seek to preserve its shape. Poach gently until done (say 3 hours), or roast carefully in a low oven on on a spit Uncover to brown for the last hour, or you can gild it in the ancient fashion by painting with a glaze of flour, egg yolk and saffron, before browning. Re-assemble the swan in its glory (you will have to use some wire) and serve with due ceremony, with the reduced stock as gravy.
Easier to have your swan stuffed by a taxidermist, and serve a good duck ballotine produced from underneath it- few will know the difference.
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