Cut each veal scallop horizontally into 2-inch widths.
In a bowl, combine the flour, salt and pepper. Dredge each piece of veal in the flour mixture and shake off excess.
In a large saute pan, heat the olive oil over medium-high heat, then add butter. Saute veal in 2 batches until lightly golden on both sides. Remove veal and set aside.
Turn heat down to medium, add the scallions and cook until tender-crisp. Add the capocolla and saute until softened, stirring constantly, about 1 minute. Stir in the mushrooms and saute, stirring constantly, for about 1 to 2 minutes.
Return the veal to pan and spoon most of the mushroom mixture on top. Pour in Marsala, turn heat to high and cook uncovered, stirring constantly, until wine is slightly reduced, for about 2 minutes.
To serve, arrange the veal on a large platter; spoon the mushroom-wine sauce on top. Garnish with minced parsely and serve immediately