Chicken Saltimbocca

Name: Chicken Saltimbocca
Ingredients: 1/2 cup unbleached all-purpose flour; Ground black pepper; 8 thin boneless, skinless chicken breast cutlets (about 2 pounds), trimmed of ragged edges as necessary; 1 tablespoon minced fresh sage leaves, plus 8 large leaves (optional); 8 thin slices prosciutto cut into 5- to 6-inch-long pieces to match chicken (about 3 ounces); 4 tablespoons olive oil; 1 1/4 cups dry vermouth or white wine; 2 teaspoons juice from 1 lemon; 4 tablespoons unsalted butter, cut into 4 pieces and chilled; 1 tablespoon minced fresh parsley leaves; Table salt