after protesting that he is not worthy , he stands , puts his hand over his heart , and recites `` all praise to the haggis , '' a scottish poem he had apparently picked up in his travels in the north of england and dedicated to a particular savory dish made of sheep 's pluck-the liver , heart , and lungs of an unfortunate sheep-cooked with onions and stuffed in that same poor sheep 's stomach , baked , and brought steaming out to great acclaim from the lucky dinner guests .