We will not tell you that the cheeseburger served at the Billy Goat Tavern is a gourmet’s delight. Far from it. It is made of a beef patty so thin that it cannot be cooked rare; the cheese on top is impure, adulterated American. Side dishes? There are none, other than potato chips. If, like us, you are a devotee of hash house cuisine, it is a meal that will quicken your pulse.