In a 1 gallon plastic food bag mix all of the above ingredients with the chicken. Seal bag and turn to coat meat. Chill at least 30 minutes or up to 2 hours turning bag occasionally.
Prepare BBQ. When medium hot lay chicken breasts on grill. Cook turning occasionally until cooked thoroughly. Baste chicken often with marinade during the 1st 5 minutes of cooking and then DISCARD the remaining marinade.
Spoon Wild West Sauce equally onto plate. Set a chicken breast in sauce serve with rice and vegetables.
In a 2-3 quart sauce pan combine the mango and the remaining ingredients. Bing to a boil of medium-high heat. Reduce heat and simmer, stirring occasionally until reduced to 2 cups, about 25 minutes.
Pour mixture into a blender and whirl until smooth. Serve warm If making up to 2 days ahead, let cool, then chill airtight; reheat until steaming. (can be made up to 2 days ahead).