Preparation Whisk both cornmeals in bowl to blend. Bring broth to boil in heavy medium saucepan over medium-high heat. Gradually whisk in cornmeal. Reduce heat to medium-low; whisk constantly until mixture boils and becomes very thick, about 5 minutes. Remove from heat. Whisk in 1/2 cup Parmesan; season with salt and pepper. Pour polenta into 8 x 8 x 2-inch baking pan; smooth top. Cool until firm, at least 30 minutes, or cover and chill overnight. Preheat broiler. Cut polenta into 16 squares; brush generously with oil. Arrange polenta, oiled side down, on small baking sheet. Brush top of polenta with oil. Broil until heated through and golden brown, about 3 minutes per side. Transfer to platter. Sprinkle with 1/2 cup Parmesan.
Preparation Whisk both cornmeals in bowl to blend. Bring broth to boil in heavy medium saucepan over medium-high heat. Gradually whisk in cornmeal. Reduce heat to medium-low; whisk constantly until mixture boils and becomes very thick, about 5 minutes. Remove from heat. Whisk in 1/2 cup Parmesan; season with salt and pepper. Pour polenta into 8 x 8 x 2-inch baking pan; smooth top. Cool until firm, at least 30 minutes, or cover and chill overnight. Preheat broiler. Cut polenta into 16 squares; brush generously with oil. Arrange polenta, oiled side down, on small baking sheet. Brush top of polenta with oil. Broil until heated through and golden brown, about 3 minutes per side. Transfer to platter. Sprinkle with 1/2 cup Parmesan.