When I think of the Mast Grill, I visualize those former hockey pucks sitting in a pool of "liquid' waiting to be served. Best bet is to ask for the patties to be brushed with butter and grilled and then load up the burger with sautéed onions, mushrooms, fresh onions, pickles, horseradish, mayo, ketchup and mustard.
Make sure you have a stiff drink to wash it down.