To prepare the cuttlefish, chop the cuttlefish tentacles and wings until very fine. Cut the cuttlefish bodies in half lengthways and stack one half on top of the other in vacuum-pack bags and seal. Freeze the cuttlefish bodies in the bags, for at least two hours, until frozen solid.
Heat a frying pan until hot, add the minced tentacles and wings and cook, over a medium heat, until all the liquid comes out. Drain the cuttlefish mince, discarding the liquid.
In a separate frying pan, add the olive oil and gently fry the shallot and garlic with the bouquet garni, until softened.
Add the cooked chopped cuttlefish, parsley and tomato purée to the frying pan and cook for 5-10 minutes.
Add the brandy and cook until it has reduced in volume, add the wine and reduce in volume again, by half.
Add the chilli flakes and top up the pan with water, until just covering the pan contents. Bring the pan up to the boil, then reduce the heat to a simmer and cook for 15 minutes until the cuttlefish is tender, and the volume of liquid has reduced. Check the seasoning, and add salt and freshly ground black pepper to taste.
Just before serving, bring a pan of water up to the boil. Take the frozen cuttlefish bodies out of the freezer and remove from the vacuum-pack bags. Thinly slice the frozen cuttlefish bodies, into 2mm/⅛in slices. Drop the cuttlefish slices into the boiling water and cook for 10-15 seconds.
Drain well and mix with the softened butter, salt and freshly ground black pepper.
To serve, spoon the cuttlefish slices into serving bowls and spoon the cuttlefish ragout on top. Finish with some grated parmesan and chopped parsley.