Mix the first 4 ingredients; it will be thick. Mix all dry ingredients and gradually add to batter. If using self rising flour, only add the baking soda. Mix together; fold in grated carrots and walnuts (optional). Add water; mix well. Bake at 350 for 55 to 60 minutes, depending on what type of pan you use; I like the bunt pan. Let cool and frost with cream cheese frosting.