How to Make It
Combine rum, mango, and habanero in the bowl of a food processor; process until smooth. Pour mango mixture into a small saucepan; bring to a boil. Stir in vinegar, butter, and 1/8 teaspoon salt; reduce heat, and simmer 6 minutes or until reduced to 1 cup.
Combine remaining 3/8 teaspoon salt, garlic powder, and next 5 ingredients (through allspice) in a small bowl. Rub oil evenly over chicken; sprinkle evenly with spice mixture.
Heat a grill pan over medium-high heat. Coat pan with cooking spray. Arrange chicken on pan; grill 5 minutes on each side or until done. Remove chicken from pan. Let stand 5 minutes. Cut across the grain into thin slices. Serve with mango sauce.