Heat the oil in a pan, sauté the onion and potatoes for approx. 5 mins. Pour in the stock, bring to the boil, reduce the heat, cover and simmer for approx 20 mins. until soft, then puree. Pour in the cream, season.
Heat the oil in a frying pan, add the meat, nuts and rosemary, stir fry over a medium heat for approx. 5 mins.
Serve the soup in bowls, add the crème fraîche and crunchy topping.