Wash potatoes and cook covered with boiling water for 15-20 minutes. Then rinse with cold water, peel and leave to rest. Peel onions and slice into fine rings. Wash cucumber, cut into thin slices. Mix yoghurt and crème fraîche.
Season with salt, pepper and lemon juice. Wash chicken breasts and pat dry. Remove fillets with skin from the bones. Push sage leaves under the skin and pin with wooden skewers. Cook on the hot grill for 15-20 minutes, turning. In the meantime, cut potatoes into slices for the salad. Mix with prepared cucumber and onions. Heat up the stock and pour over it. Wash the apple, remove seeds, cut into fine slices and sprinkle with lemon juice.
In the meantime, cut potatoes into slices for the salad. Mix with prepared cucumber and onions. Heat up the stock and pour over it. Wash the apple, remove seeds, cut into fine slices and sprinkle with lemon juice. Serve potato salad, apple slices and yoghurt sauce garnished with dill and sage. Serve with grilled fillets