Macsween, a popular maker of the distinctive Scottish dish, has developed a recipe for the U.S. market that swaps sheep lung for lamb heart as a main ingredient. Scotland, Burns, Robert (1759-96), Cooking and Cookbooks, Meat, Sausages, Beef, Lamb, internal-storyline-no Macsween, a popular maker of the distinctive Scottish dish, has developed a recipe for the U.S. market that swaps sheep lung for lamb heart as a main ingredient. NYT > Business