Preheat the oven to 180C/350F/Gas 4. Remove the breasts from the birds, season with crushed black pepper and sea salt and set aside.
Place the pigeon carcasses in a roasting tin and season with the mustard, fennel seeds, thyme, juniper berries and garlic. Tuck the bay leaf into the cavity of one of the birds then roast them in the oven for 30 minutes.
To make the stock, heat the oil in a large saucepan and brown the celery, carrot and shallots. Add the roasted carcasses and a splash of the wine and cook for three minutes, and set aside the roasting tin to make the sauce later. Add the game and chicken stocks to the saucepan with most of the remaining wine, reserving a little wine for the sauce and the risotto, and leave to simmer for 45 minutes. Strain the stock into a clean pan, measure 150ml/5fl oz of the stock and set aside for the sauce.
For the risotto, place the pancetta in a dry pan and cook over a medium to high heat until crisp. Add the butter and shallot and cook gently until the shallots are soft. Add the rice and stir well for about three minutes, then add a splash of the wine and stir until the wine is absorbed.
Add the stock, ladle by ladle, stirring all the time, and cook for about 15 minutes, or until the rice is cooked but still has a slight bite. When the rice is cooked, add the parmesan and leave aside to rest for 2-3 minutes.
Meanwhile, cook the pigeon breasts in the butter in a very hot frying pan for 2-3 minutes on each side. Remove from the pan and leave to rest in a warm place.
For the sauce, deglaze the roasting tin with a splash of the reserved wine. Add 150ml/5fl oz of the stock, reduce and season. Gradually whisk in the cold cubes of butter to form an emulsion and season, to taste, with sea salt and freshly ground black pepper.
Just before serving, heat a little butter in a clean frying pan and re-fry the pigeon breasts with a little chopped thyme for 2-3 minutes, then remove from the pan and slice each breast in two. Place the risotto in four deep plates. Top each with three slices of pigeon followed by the sauce. Finely shave the parmesan and black truffles and scatter on the side of the plate with Cyprus salt or sea salt flakes.