Expert Answer:

Lisa Featherby, Gourmet Traveller food editor, writes:
Funnily enough, the name 'beef cheek' refers to the facial cheek muscle of a cow. It's a very tough and lean cut of meat and is most often used for braising or slow cooking to produce a tender result. You may need to order them ahead from your butcher. If beef cheeks aren't available, beef brisket cut into pieces of the same weight make a good substitute.

Here are a couple of beef cheek recipes you can try at home:
Spanish braised beef cheeks with tomato bread, parsley and anchovy salad
Beef cheek onion and stout pies with thyme and onion pastry
Beef cheek ravioli with mandarin mustard fruits