1. Coat the slices of meat in flour and sauté in a frying pan with olive oil for one minute per side.
2. Remove the meat and keep hot in a container.
3. Place the potatoes cut into julienne strips in the same pan and stir them with a wooden spoon.
4. Press and cook the potatoes until they are golden and compact on both sides.
5. Remove the potatoes from the pan and keep hot.
6. Add the butter, rosemary and cutlets to the same pan.
7. Turn on the heat and once the butter has melted add the wine, the onion and the champignon and black truffle sauce.
8. Allow the flavours to blend for a few minutes and add salt and pepper to taste.
9. Dish up accompanying the cutlets with the golden potatoes.