Preheat oven to 180°C.Heat the oil in a large ovenproof frying pan. On the stove heat the oil in the frying pan, brown chicken from all sides. Peel large floury potatoes, boil them in salted water for about 10 minutes. Leave to cool then grate them. Put the potatoes into a towel and squeeze out any excess water then season the potatoes with black pepper and ground sage. Heat the duck fat or clarified butter. Make one large pattie or several small ones, cook rosti from both sides until crisp.
Drain away any excess fat from chicken, add thinky sliced onion,shallots and pears to the pan gently cook for about minutes 4- 5 minutes, stirring it all together.
For the sauce combine the sauce ingredients in a dish or bowl, whisk thoroughly add the sauce and the kaletts, transfer dish or pan to oven, cook until chicken is done.
Serve the chicken with the thick,sticky sauce poured over.
