Pounding the chicken breasts makes them even and thinner, reducing the grilling time.
Place chicken between 2 sheets of heavy-duty plastic wrap, and flatten to a 1/2-inch thickness, using a meat mallet or rolling pin. Place chicken in a shallow dish or large zip-top plastic freezer bag.
Stir together orange juice and next 7 ingredients. Reserve 1/2 cup orange juice mixture; set aside. Pour remaining mixture over chicken. Cover or seal and chill 1 hour, turning occasionally. Remove chicken from marinade, discarding marinade. Sprinkle chicken evenly with pepper and 1/2 teaspoon salt.
Coat cold grill rack with cooking spray, and place on grill. Grill chicken over medium-high heat (350° to 400°) 4 minutes on each side or until done. (Do not overcook.)
Place reserved orange juice mixture in a microwave-safe glass measuring cup; cover loosely with plastic wrap. Microwave at HIGH 1 to 2 minutes or until bubbly. Serve with chicken.
*Substitute 1 family-size tea bag or 4 single-serve tea bags for unsweetened tea mix. Microwave orange juice at HIGH for 1 minute. Steep tea bag in hot orange juice 10 minutes. Remove tea bag. Chill orange juice mixture while preparing chicken. Proceed with recipe as directed.
Note: For testing purposes only, we used Nestea Unsweetened instant iced tea mix.