Preheat the oven to 350 degrees F. Spray a Bundt pan with non-stick spray.
Using an electric mixer, mix together the butter and 2 cups of sugar in a small bowl. Add the eggs, one at a time, then add the sour cream and vanilla; mix until well blended. In a separate bowl, mix together the flour, baking powder and salt. Add half of the dry ingredients and mix until just blended, then, add the remaining dry ingredients and mix until well combined.
In another small bowl combine the remaining 1/4 c. sugar, cinnamon, and brown sugar and mix until well combined.
Pour half of the batter into the Bundt pan. Sprinkle the cinnamon sugar mixture over the batter, then pour the remaining batter over the sugar mixture. Bake until a toothpick inserted into the center of the cake comes out clean, about 50 minutes to 1 hour. Let cool until just slightly warm. Remove the cake from the bundt pan to a serving dish and sprinkle powdered sugar over the top, if desired. Very Good!