Pound your chicken cutlets between sheets of plastic wrap with a meat mallet or rolling pin so you have 4 cutlets about a ¼ inch thick.
Lay out the cutlets and put about 2 tablespoons of shredded Fontina on each cutlet.
Put 2 or 3 teaspoons of chopped sage over the Fontina and cover with a piece of the folded Prosciutto.
Carefully roll up the cutlet and tie snugly in the middle with a length of cooking twine; trim off any extra twine once tied.
Salt and pepper the rolled cutlets (rollatini) and dredge in the flour, shaking off extra flour.
Brown the rollatini on all sides over medium high heat in a cast iron or other heavy bottomed pan; remove the rollatini from the heat and cover to keep warm.
Add the sliced mushrooms and 2 teaspoons of sage with a little of the Marsala or chicken broth and scrape up any brown crusty bits stuck to the pan.
Once the mushrooms have released their moisture and begin to brown add the Marsala, lemon zest, ½ teaspoon of salt and ¼ teaspoon of black pepper, and cook over medium high heat until reduced by a half.
Add the broth and reduce by half.
Return the rollatini to the pan and coat with the sauce while cooking for about 3-4 minutes more until fully heated through.
Optional: garnish with crumbled toasted sage leaves.
