From: Stephanie da Silva
This one takes a little longer. Chop up some fresh mushrooms and onions, and saute in butter, margarine, oil, whatever until the onions are clear. Drain and set aside until cool. On cocktail bread (rye or pumpernickel), pile a mound of mushrooms and onions, grated swiss cheese, grated italian cheese (i use locatella), and bread crumbs. Broil until the swiss melts, and serve immediately.