Stuff the chicken with the lemon. Rub olive oil into the skin and season with salt and pepper, dust with the cayenne pepper and squeeze the remaining lemon half over the bird.
Roast in the oven, turning down the heat to 350F after 20 minutes. Cook until the juices run clear when the leg of the bird is pierced with the tip of a knife.
Remove the chicken from the roasting tin and keep warm whilst you make the gravy. Spoon off some of the fat from the roasting tin, then put it over a medium heat. Pour in the wine and allow to bubble up, then add the chicken stock. Bring to the boil, then season.
Serve the roast chicken with peas, gravy and maybe a dressed green salad.