In the bowl of an electric mixer beat the butter and 1 cup of the sugar for 3 to 5 minutes on medium-high speed, until light and fluffy. With the mixer on low, add the eggs, one at a time, then the sour cream and vanilla, and mix until the batter is smooth. In a separate bowl, sift together the flour, baking soda, baking powder, and salt. With the mixer on low, slowly add the dry ingredients to the batter and mix just until combined. In a small bowl, combine the remaining 1/2 cup sugar and the cinnamon.