ready in 37 min.
Gently flatten the veal with a rolling pin or mallet, until each piece is about 1/4-inch thick. Season pounded veal with salt and pepper. Dust the veal with flour, shaking off the excess. Lay a piece of prosciutto on top of each piece of veal and place 1 or 2 sage leaves on top of the prosciutto, securing prosciutto and sage with a small wooden skewer or toothpick.
Heat the oil and 2 tablespoons butter in a large skillet over medium heat. Place veal, prosciutto side down in the pan, and cook over high heat for 3 minutes, or until nearly cooked through. Turn and saute for about 2 minutes. Transfer saltimbocca to a serving platter, remove wooden skewers; set aside.
Pour off any grease in the pan. Add wine, stirring to release any flavorful bits in the bottom of the pan. Cook over high heat reducing by half. Add chicken stock and remaining tablespoon of butter, stirring to evenly incorporate. Cook until reduced by half.
Return veal to the skillet, prosciutto side up, and simmer for 2 minutes, or until veal is heated through. Check seasoning and adjust if necessary. Transfer to plates; drizzle with remaining sauce. Garnish with sage. Serve.