beefsteak vs brain mushroom

beefsteak

noun
  • The herb prepared from the leaves of the beefsteak plant. 

  • (A) steak cut from beef cattle. 

brain mushroom

noun
  • A fungus common in Europe and North America and one of several species of fungi known as false morels, especially Gyromitra esculenta. 

How often have the words beefsteak and brain mushroom occurred in a corpus of books? (source: Google Ngram Viewer )