I'm looking to brew an imperial stout that I would like to cellar for years. In your experience with homebrewing, what ingredients or techniques (e.g. chocolate, chili, cinnamon, vanilla bean, oak aging, etc.) have aged particularly well? Which ones fade with time? Does added coffee fade enough that it's not worth using in a brew you'd age? Or does it still add a subtle depth of flavor? Should most of the conditioning take place in the bottles if I'm adding ingredients in the secondary?
I'd appreciate any specifics and recipe suggestions too. I'll need to use a 5 gallon extract recipe for this batch, but feel free to suggest an all-grain recipe for future reference. Thanks!