3/4 c. butter, softened
1 1/2 c. sugar
1 1/2 t. vanilla
3 cups flour
1 1/2 t. baking powder
1 1/2 t. baking soda
1/4 t. salt
1 1/2 c. sour cream
1/2 c. brown sugar, packed
1/2 c. finely chopped nuts
1 1/2 t. ground cinnamon
Preheat oven to 350 degrees. Grease tube pan (10x4 inches), 12 cup bundt cake pan or 2 loaf pans (9x5x3 inches). Combine butter, sugar, eggs and vanilla in large mixer bowl. Beat on medium speed for 2 minutes. Mix in flour, baking powder, baking soda and salt alternately with sour cream.
To prepare filling, in a separate bowl combine the brown sugar, nuts and cinnamon; set aside.
For tube or bundt cake, spread 1/2 of the batter (about 2 cups) in pan and sprinkle with 1/3 of filling (about 6 tablespoons); repeat twice.
For loafs, spread 1/4 of the batter (about 1 1/2 cups) in each pan and sprinkle each with 1/4 of the filling (about 5 tablespoons), repeat once.
Bake until wooden pick inserted near center comes out clean, about 1 hour. Cool slightly; remove from pan(s).
Notes: This tastes super yummy, but trying to remove the loaf from the pan causes the top layer of filling to get all over the place. It's best to slice it in the pan (not if you're using a non-stick pan!) or put the bulk of the filling inside the loaf instead of on the top.