½ cup firmly packed brown sugar
1-1/2 teaspoons cinnamon
1 cup chopped walnuts or pecans (optional)
3 cups all-purpose flour
1-1/2 cups sugar
3 teaspoons baking powder
1 teaspoon baking soda
½ teaspoon salt
1 cup butter or margarine, softened
1 cup sour cream
1 teaspoon vanilla
Combine brown sugar, cinnamon and nuts in a small bowl. Set aside
Combine flour, sugar, baking powder, baking soda and salt in a mixer bowl. Add butter, sour cream and vanilla. Mix for about 1 minute. Scrape down bowl and add eggs, one at a time. Mix for about 1 minute.
Spread half of batter in a greased and floured pan. I used a 9 inch spring form pan for this one. Sprinkle with half of the cinnamon-sugar mixture. Spread remaining batter on top and sprinkle with the remaining cinnamon-sugar.
Bake at 350 for 55-60 minutes or until toothpick in middle comes out dry.