This recipe is a special favorite with our guests and is requested over and over. -Cleftstone Manor, Bar Harbor, Maine
Preheat oven to 350 degrees F. Grease and flour a 10-inch tube pan.
In a bowl, combine flour, baking powder, baking soda, and salt. Set aside.
In another bowl, cream butter and sugar with an electric mixer. Add eggs, one at a time, beating well. Add flour mixture alternately with sour cream and vanilla to batter.
In a separate bowl, combine brown sugar, nuts, and cinnamon and reserve ½ cup. Toss the remainder with the blueberries.
Spread one third of batter in the prepared pan. Sprinkle with half of the berry mixture, then spread another third of batter and sprinkle with remaining berry mixture. Top with remaining batter. Sprinkle on ½ cup reserved cinnamon mixture. Bake for 60 to 65 minutes. Cool for 10 minutes before removing from the pan.