Preparation 1. Bring water to boil in heavy-bottomed 4-quart saucepan over medium-high heat. Stir in salt and baking soda. Slowly pour cornmeal into water in steady stream, while stirring back and forth with wooden spoon or rubber spatula. Bring mixture to boil, stirring constantly, about 1 minute. Reduce heat to lowest possible setting and cover.2. After 5 minutes, whisk polenta to smooth out any lumps that may have formed, about 15 seconds. (Make sure to scrape down sides and bottom of pan.) Cover and continue to cook, without stirring, until grains of polenta are tender but slightly al dente, about 25 minutes longer. (Polenta should be loose and barely hold its shape but will continue to thicken as it cools.)3. Remove from heat, stir in butter and Parmesan, and season to taste with black pepper. Let stand, covered, 5 minutes. Serve, passing Parmesan separately.