Pour some water in a large pan - enough so that it will cover the chickens. Season with the bouillon, peppercorns and coriander seeds then add the vegetables thyme and bay leaves. Simmer for 10 minutes.
Remove the wings and parsons nose from the chicken leaving just the crown of the bird. Place the garlic in the cavity, season and poach the chicken, together with its wings, for 10 -15 minutes, depending on its size. Remove and leave to rest for 5 minutes.
Meanwhile make the sauce. Season and sauté the shallots, thyme and garlic in olive oil until golden. Add the mushrooms and a little more olive oil. Sauté for a good 5-6 minutes. Add the wine and allow to lightly evaporate. Add 3 large ladles of the chicken cooking stock and leave to cook out for a further 6 minutes, allowing the velouté to reduce by a third. Add the cream and simmer for 5 minutes. Pass the mixture firmly through a sieve and return to the heat, taste and season.
Carefully remove the breasts from the chicken carcass, pat dry and season. Heat some oil in a non-stick pan and fry the chicken breasts until the skin is beautifully crisp and golden approx 4 -6 minutes. Finally add a knob of butter to the chicken and baste over the meat for the final minute of cooking to keep it tender. Remove the chicken and slice each breast in half, horizontally and open into a fan shape.
Add the parsley to the velouté and mix well. To serve, season the 'inside' of your opened chicken breast for maximum flavour.