Whip butter, sugar, eggs, and vanilla.
Add buttermilk and water. Mix thoroughly, scraping sides of bowl.
Add cocoa, cinnamon, salt, baking powder, baking soda, and flour. Mix.
Pour into greased bread pan.
In a separate bowl, mix together ingredients for topping.
Sprinkle evenly on top of batter.
Bake at 350 for 35-40 minutes.