Keeping it Safe
Use a visual test to ensure boneless chicken breasts are cooked through. Cut small slit in thickest part of each chicken piece. If the meat is totally white with no pink color, it is safe to eat.
Use Your Broiler
Marinate chicken as directed. Preheat broiler. Place chicken on rack of broiler pan. Broil, 4 to 6 inches from heat, 6 minutes on each side or until cooked through, brushing frequently with the reserved mustard mixture.