Preparation Butter 9-inch-diameter glass pie dish. Bring broth to boil in heavy medium saucepan. Gradually whisk in corn meal. Reduce heat to medium and whisk constantly until mixture thickens, about 6 minutes. Remove from heat. Add cheese and 1 1/2 tablespoons butter; stir until cheese melts. Stir in chopped walnuts and rosemary. Season with salt and pepper. Transfer polenta to prepared dish; using buttered knife, spread evenly. Cool until polenta is firm, at least 1 hour. Line baking sheet with foil. Cut polenta into 8 wedges. Transfer wedges, bottom side up, to prepared sheet. Dot wedges with 1 1/2 tablespoons butter. Place 1 walnut half in center of each wedge. (Can be made 1 day ahead. Cover and chill.) Preheat oven to 350?F. Bake polenta until heated through, about 12 minutes.
Preparation Butter 9-inch-diameter glass pie dish. Bring broth to boil in heavy medium saucepan. Gradually whisk in corn meal. Reduce heat to medium and whisk constantly until mixture thickens, about 6 minutes. Remove from heat. Add cheese and 1 1/2 tablespoons butter; stir until cheese melts. Stir in chopped walnuts and rosemary. Season with salt and pepper. Transfer polenta to prepared dish; using buttered knife, spread evenly. Cool until polenta is firm, at least 1 hour. Line baking sheet with foil. Cut polenta into 8 wedges. Transfer wedges, bottom side up, to prepared sheet. Dot wedges with 1 1/2 tablespoons butter. Place 1 walnut half in center of each wedge. (Can be made 1 day ahead. Cover and chill.) Preheat oven to 350?F. Bake polenta until heated through, about 12 minutes.