Wash chickens thoroughly inside and out and pat dry. Wash sage, dab dry and pluck the leaves from the stems. Season chicken inside and out with salt and pepper and put half of the sage in the abdominal cavity.
Tie the legs and wings together with kitchen yarn. Place the chicken with the breast side on the fat pan of the oven, cover with flakes of fat and roast in the preheated oven (electric cooker: 200 °C / gas: level 3) for approx. 30 minutes.
In the meantime, wash and peel the potatoes and put them in cold water. Bring shallots to the boil briefly, pour onto a sieve and rinse with cold water. Remove the shallots from the skin. Chop the olives. Turn the chicken, cover with bacon and remaining sage.
Pour in white wine and 1/8 litre of stock and fry for another 10 minutes. Spread potatoes and shallots around the chicken, season with salt and pepper and fry everything for another 35 minutes. 5 minutes before the end of the cooking time, pour on the remaining stock and mix olives with the potatoes and shallots.
Gradually stir the cocoa with the liqueur until smooth. Heat milk, stir in cocoa, bring to the boil while stirring. Remove from the stove. Whip cream until stiff. Pour cocoa milk into 4 cups. Add cream, sprinkle with cocoa, wash parsley, dab dry and chop, except for a little to garnish. Arrange chicken and olive vegetables on a plate. Sprinkle with parsley and serve garnished.