1 c. chopped pecans
2/3 c. brown sugar
2 tbsp. butter, melted
1 1/2 tsp. ground cinnamon
1/2 c. sour cream
1 (27 1/4 oz.) pkg. cinnamon streusel cake mix

Topping: Stir together pecans, brown sugar, butter, and cinnamon. Set aside.

Prepare cake mix as directed on package. Also stir the sour cream into the prepared batter. Pour 2/3 batter into a greased and floured pan. Then sprinkle batter with the streusel mix from package. Then pour remaining batter. Sprinkle with reserved topping. Drizzle icing on top.