cup of tea vs gunpowder tea

cup of tea

noun
  • Used other than figuratively or idiomatically: see cup, tea. A cup or mug with tea in it. 

  • three 

  • Whatever suits or interests one. 

gunpowder tea

noun
  • A form of Chinese green tea in which each leaf has been rolled into a small round pellet. 

How often have the words cup of tea and gunpowder tea occurred in a corpus of books? (source: Google Ngram Viewer )