I did a Chocolate Espresso Stout that called for 8 ounces of powdered cocoa. The espresso part was the dominate flavor when I kegged it three months ago, but now the espresso is smoothing out, and it's a very nice beer. I'm thinking that I would let it age for a month or so and then, if necessary, hit it with some vanilla beans.
It's pretty amazing how the flavors move around over time. Good Luck...
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