Great question — answering as the UphillTech team:
This is likely a fine substitution. I haven't tried King Goblin myself, but looking around online, I see some good signs: The description of the beer on drizly (presumably provided by the manufacturer) mentions chocolate malt, and goes on to describe it as: an indulgently rich, full, smooth beer The reviews on beeradvocate consistently mention flavor notes such as: Chocolate "Dark fruit" or raisins Caramel Nutty/toasty Toffee malt Burnt sugar These are many of the same qualities that you'd be looking for in a stout used for cooking. Finally, this discussion thread from a homebrewing forum describes efforts to replicate it by hobbyists, and the comments there suggest that the original beer...
Full answer by A_S00: https://cooking.stackexchange.com/a/117785 (CC BY-SA 4.0).
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