// take order for table 1 and move on...
orderNonBlocking(['Coke', 'Iced Tea'], function(drinks){
  return serveOrder(drinks);
});

// take order for table 2 and move on...
orderNonBlocking(['Beer', 'Whiskey'], function(drinks){
  return serveOrder(drinks);
});

// take order for table 3 and move on...
orderNonBlocking(['Hamburger', 'Pizza'], function(food){
  return serveOrder(food);
});