Lightly oil a 9 X 5 X 3-inch loaf pan. Bring a large pot of water to a boil. Add salt and gradually pour cornmeal into water, stirring constantly to avoid lumps. Let mixture come to a boil, reduce heat to medium and cook, stirring frequently, for 40 minutes. Stir in butter, 6 tablespoons of the Parmesan cheese and sage, then pour into loaf pan. Cover with wax paper and set aside to become firm, 15 minutes. Heat oil in a large skillet. Add onion and sauté over medium-high heat until translucent, about 5 minutes, then stir in mushrooms and sauté 1 minute more. Pour in Silver Palate Thick and Sassy Pasta Sauce and red wine. Season with black pepper. Allow mixture to simmer while finishing polenta. Cut polenta into slices and place on lightly oiled baking sheet. Sprinkle on remaining Parmesan and run under broiler until cheese is lightly colored and polenta is hot. Place slices on individual warmed plates, ladle on sauce and serve at once.