Rub chicken with jerk seasoning. In a large skillet coated with cooking spray, cook chicken in 1/2 teaspoon oil over medium heat for 3-4 minutes on each side or until juices run clear. Remove and keep warm.
In the same skillet, saute the asparagus, pineapple and onions in remaining oil for 2-3 minutes or until tender. Combine the cornstarch, pineapple juice and mustard until smooth; gradually stir into the pan. Bring to a boil; cook and stir for 1 minute or until thickened. Serve with chicken and rice.