Place flour into a large shallow bowl. Cut the turkey breast horizontally in half; flatten each half with a meat mallet to ½ inch thickness. Sprinkle with pepper. 

Dip the meat into the flour to coat both sides then shake off excess. 

In a large skillet, heat the oil and one half of butter over medium heat.

Place a slice of prosciutto and then two sage leaves on each piece of turkey. Using flat toothpicks, secure the sage leaves and prosciutto slices.

Heat a medium skillet then add oil. When the oil is hot, place the turkey breast in the pan, sage-and-prosciutto-side down. Cook for 2-4 minutes, depending on the thickness of the cutlet, or until it is no longer pink. Turn the meat over and cook for another 1-2 minutes. Remove from the pan, but keep warm.

In the same pan heat the rest of your butter over medium-high heat. Shake any remaining seasoned flour from the plate into the skillet and give it a few stirs. Turn the heat down to medium to add the wine., Once you’ve added your wine, turn the heat back up to medium-high, and cook until the liquid is slightly reduced, stirring continuously to loosen any browned bits from the bottom of the skillet. Let it reduce further by half and then add the stock. Finish your cooking on medium heat, stirring constantly, until the pan sauce reaches the desired consistency. 

Add salt and pepper to taste. 

Remove the toothpicks from the meat and spoon the sauce over the meat before serving.