2 c. sugar
2 c. flour
1/4 c. cocoa
1 tsp. baking soda
1 tsp. salt
1/2 c. oil
1/2 c. butter, softened
1 c. water
2 eggs
1 tsp. vanilla
1/2 c. sour cream

Mix together first 5 ingredients in large bowl. Make a well in dry ingredients and add oil, butter, water, eggs, and vanilla. Beat ingredients together until smooth, then fold in sour cream. Pour into greased 10 x 15 inch cake pan. Bake at 350 degrees about 30-35 minutes.

ICING:

1/2 c. butter
1/4 c. cocoa
3 tbsp. sour cream
1 tsp. vanilla
3 c. xxx powdered sugar
1 c. broken nuts

Combine ingredients into saucepan and cook over low heat until well blended. Spread over brownies. Sprinkle with nuts.