In a large mixing bowl, cream the butter and 2 cups of sugar until fluffy. Add vanilla. Add eggs one at a time, beating well after each addition. Combine flour,baking powder, baking soda and saly; add alernatley with sourcream, beating just enough after each addition to keep batter smooth. Spoon 1/3 of the batter into a greased 10-inch tube pan. combine cinnamon, nuts and remaining sugar; sprinkle 1/3 over batter in pan. Reapeat layers 2 more times. Bake at 350F for 70 minutes. Remove from pan to a wire rack to cool completely.