In a large saucepan, bring chicken stock to a boil, then lower heat and simmer until broth reduces by half. Meanwhile, in a medium saucepan, heat oil over medium heat, add onion and cook until onion softens and starts to brown, about 5 to 8 min. Add cooked onion to reduced broth, stir in remaining ingredients, bring to a boil, then lower heat and simmer until reduced to a thick sauce, about 20 min. Transfer mixture to a blender or food processor and puree until smooth.
Serve warm with any protein marinated and grilled with our Bajan marinade.