Chocolate Sour Cream Pound Cake

1 cup
butter
2 cups sugar
1 cup firmly packed brown sugar
6 large eggs
2 1/2 cups all-purpose flour
1/4 teaspoon baking soda
1/2 cup cocoa
8 oz. carton sour cream
2 teaspoons vanilla
Powdered sugar (optional)
Beat butter at medium speed with electric mixer, about 2
minutes until soft and creamy. Gradually add sugars,
blend 5 minutes. Add eggs one at a time, beating until
the yellow disappears. Combine flour, baking soda, and
cocoa. Add dry mixture to creamed mixture alternately
with sour cream. Mix at low speed just until blended
after each addition. Stir in vanilla. Spoon batter into
greased and floured 10" tube pan. Bake at 325 for 80
minutes until toothpick comes out clean. Cool in pan on
wire rack 10-15 minutes. Remove from pan and cool on
wire rack. Sprinkle with powdered sugar if desired.