Feedback for an unusual beer. Imperial German Chocolate Stout

Well, I figured I'd give it a shot and try and design a recipe. I'm really not sure how it will turn out, so I figured I would hand this off to you guys to see if you see any big mistakes. I want this to be a sweet beer that reminds people of german chocolate cake (if that wasn't obvious from the title). Thanks for your feedback!


Recipe Specifications
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Batch Size (fermenter): 5.00 gal
Boil Size: 6.00 gal
Bottling Volume: 5.00 gal
Estimated OG: 1.109 SG
Estimated Color: 37.7 SRM
Estimated IBU: 43.8 IBUs
Brewhouse Efficiency: 63.00 %
Boil Time: 60 Minutes

Ingredients:
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Amt Name Type # %/IBU
10 lbs Pale Malt (2 Row) US (2.0 SRM) Grain 1 52.6 %
1 lbs Wheat, Flaked (1.6 SRM) Grain 4 5.3 %
1 lbs Chocolate Malt (350.0 SRM) Grain 3 5.3 %
1 lbs Caramel/Crystal Malt -120L (120.0 SRM) Grain 2 5.3 %
2.00 oz Horizon [9.10 %] - Boil 60.0 min Hop 7 43.8 IBUs
16.00 oz Chocolate Powder (Boil 5.0 mins) Flavor 8 -
1 lbs Milk Sugar (Lactose) (0.0 SRM) Sugar 5 5.3 %
5.00 lb Toasted Coconut Flakes (Secondary 2.0 we Flavor 10 -
5 lbs Amber Dry Extract (12.5 SRM) Dry Extract 6 26.3 %
1.0 pkg Belgian Abbey II (Wyeast Labs #1762) [12 Yeast 9 -


Mash Schedule: Single Infusion, Medium Body
Total Grain Weight: 19 lbs
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Name Description Step Temperat Step Time
Mash In Add 16.25 qt of water at 168.2 F 152.0 F 60 min
Mash Out Add 9.10 qt of water at 203.1 F 168.0 F 10 min

My concern would be with the coconut flakes. Does that have oils? If so you will kill head retention. Maybe you could get a coconut flavoring? It also looks like a "kitchen-sink" recipe. Maybe you could brew a base brew and ferment, then separate them into 1 gallon volumes to try the various other components - cocoa powder, lactose, coconut etc?

No matter what, let us know how this turns out.