Streusel:
3 Tbsp. Brown Sugar
3 Tbsp. Flour
1 1/2 tsp. Cinnamon
3 Tbsp. Butter
1 c. Walnuts or Pecans, chopped

In small bowl combine brown sugar,flour,cinnamon and butter, using a pastry blender until crumbly.
Stir in nuts.
Set aside.

Cake:
3/4 c. Butter, softened
1 c. Granulated Sugar
1/2 c. Brown Sugar
3 Eggs
2 1/2 c. Flour
1/2 c. Whole Wheat Flour
1 Tbsp. Baking Powder
1 1/2 c. Sour Cream
2 tsp. Vanilla

In mixing bowl cream butter until smooth.
Add sugars.
Add eggs, one at a time.
In small bowl combine flours and baking powder.
Add flour mixture alternately with sour cream to creamed butter mixture.
Beat on low until combined.
Mix in vanilla.
Grease and flour a 10″ tube pan.
Spoon half of batter into pan.
Sprinkle with streusel mixture.
Spoon remaining batter over streusel mixture.
Bake 50-55 minutes at 350°F.
Until toothpick inserted near center comes out clean.
Let cool 10 minutes before removing from pan.
Place cake on serving plate and drizzle with icing.

Icing:
1 c. Powdered Sugar
1/4 c. Pure Maple Syrup

Stir together until smooth.