Bring broth, cream, and salt to boil in medium saucepan. Gradually whisk in polenta; reduce heat to medium-low and simmer 10 minutes, stirring often. Add corn; increase heat and bring to boil. Reduce heat to medium-low; cook until polenta is soft, thick, and creamy, stirring often, about 15 minutes. Stir in butter and season to taste with salt and pepper. Serve hot.
