title_body: How can I brew a black lager?
upvoted_answer: A black lager, or perhaps a schwarzbier, really is a lager.  Aside from the difference in the fermentation process, there will be some difference in your base ingredients, as a schwarzbier will focus less on the chocolates or coffee flavor of a stout.
  
  I suspect you may find significantly more information in homebrew.stackexchange.com, as hunse suggests.  We would love to go into all sorts of detail over there!