braise vs hot up

braise

verb
  • To cook in a small amount of liquid, in a covered pan, somewhere between steaming and boiling. 

noun
  • A sauce used for braising. 

  • A dish (usually meat) prepared by braising. 

  • Pagellus bogaraveo, syn. Pagellus centrodontus (sea bream) 

hot up

verb
  • To become more heated. 

  • To make or become more sexually appealing, enticing or exciting. 

  • To increase in temperature. 

How often have the words braise and hot up occurred in a corpus of books? (source: Google Ngram Viewer )