Preheat oven to 325F.
Combine 1 cup sugar and 2 tsp cinnamon in a bowl and set aside.
Generously grease a 9 inch Bundt pan with butter, being careful to make sure that all of the creases and the inside tube gets covered.
Dust the inside of the pan with enough cinnamon sugar to coat the surface; approximately 1/4 - 1/3 cup. Return any remaining sugar to the rest that is leftover.
Sift together the flour, baking powder, baking soda and salt. Set aside.
Beat the butter on medium speed for 1 minute.
Add the white sugar and mix for 3 minutes, until light and fluffy. Scrape down the bowl and blade.
Add the brown sugar and mix for 2 minutes until the mixture looks light brown and uniform in color.
Add the eggs one at a time, beating each for 1 minute.
Mix in the vanilla.
Add the flour mixture alternately with the sour cream and then beat well until everything is incorporated.
Fold in the chopped apples.
Spread half of the batter into the prepared pan. Sprinkle with 3/4 of the remaining cinnamon and sugar mixture. Spread the rest of the batter into the pan and sprinkle the remaining sugar mixture over the top.
Bake for 60 – 65 minutes, or until a toothpick inserted into the cake comes out clean. Allow to cool for 10 minutes before inverting onto a wire rack to cool completely.