Cut the veal into 3 x 4-inch pieces (7-10cm).
Pound the veal to become thin.
Place a slice of prosciutto on top of each piece of veal and top with a leaf of fresh sage and roll up.
Skewer with a toothpick to hold together and sprinkle the bottom sides with ? teaspoon of the salt.
Pour the oil and 1 tablespoon of the butter into a large saute pan and cook over high heat until almost smoking.
Add the veal and saute 30 seconds on each side, shaking the pan to prevent sticking.
Transfer the veal to another dish and pour the oil out of the pan.
Place the pan back on the heat and deglaze with the wine, cooking until reduced to a thick glaze, about 2 minutes.
Pour in the stock and the remaining salt and the pepper, and bring to a boil. Reduce the heat to a simmer, return the meat to the pan and cook for 2 minutes.
While the meat is heating, mix the remaining soft butter with the flour to make a thick paste. Remove the meat from the pan and place on a serving dish.
Bring the stock to a boil and add the butter/flour paste, one spoonful at a time, whisking well until the sauce is thick. Pour it over the meat and serve.
If you’d like more sauce, increase the wine by 2 tablespoons the stock by ¼ cup, and the flour/butter mix by 1 teaspoon of flour.