When the flame has gone out, or the whisky has reduced, add the chicken stock. Scrape the browned bits from the bottom of the skillet.
Simmer until the stock has reduced by about one-third.
Add the cream and mustard. Simmer gently until the sauce thickens enough to lightly coat the back of a spoon.
Stir in the lemon juice. Taste and adjust the salt and pepper.
Return the chicken to the skillet for no more than a minute, turning it once to warm it through. Remove it promptly so it does not overcook.
To Serve
Place a restrained pool of whisky cream sauce slightly off-center on each warm plate.
Arrange two chicken cutlets over the sauce, slightly overlapping. Turn the upper cutlet at an angle so the arrangement looks natural rather than symmetrical.
Place several generously sized roasted potato pieces to one side, leaving a little space between them.
Set two roasted tomato halves nearby, separated slightly from the chicken. Tuck a very thin orange slice partly beneath or beside the tomatoes.
Lay one or two large sprigs of Italian parsley across the chicken.
Serve immediately.