Heat oil in a heavy skillet over medium heat. Add prosciutto and garlic and saute for a couple of minutes. Add wine, lemon juice and sugar and simmer for 5 minutes. Transfer to a bowl and cool completely. Add salt and pepper, to taste. Toss together spinach, mushrooms, walnuts and cheese in a bowl. Give dressing a quick stir before tossing with the salad.
A viewer or guest of the show, who may not be a professional cook, provided this recipe. It has not been tested for home use.