In a small saucepan over medium heat, heat oil until hot, but not smoking. Add onions and saute, stirring occasionally, until transparent, 5 to 7 minutes. Add ginger and garllic and saute, stirring for 1 minute. Add the rum, vinegar, ketchup, molasses, sugar, allspice and mace and bring just to a boil. Reduce the heat to low and simmer gently for 20 minutes. Remove from heat and season to taste.
Makes about 1 quart of sauce.
Source: "License to Grill" John Willoughby and Chris Schlesinger
Recipe by: P.B. Post: 07/03/97 Posted to MC-Recipe Digest V1 #655 by Raymond <email@example.com> on Jul 2, 1997