1/2 c. butter
1 c. brown sugar
2 c. flour
1/2 tsp. baking soda
1/4 tsp. salt
1 egg
1 tsp. vanilla
2 (1 oz.) squares unsweetened chocolate (melted and cooled)
3/4 c. sour cream
1/2 c. chopped California walnuts

MOCHA FROSTING:

1/4 c. soft butter
2 tbsp. cocoa
2 tsp. instant coffee
Dash of salt
3 c. confectioners' sugar
3 tbsp. milk
1 1/2 tsp. vanilla