1. Preheat oven to 400°.
2. Remove and discard giblets and necks from hens. Split hens in half lengthwise. Place hen halves, breast sides up, in a roasting pan coated with cooking spray.
3. Combine mustard and jelly. Brush mustard mixture over hens; sprinkle evenly with pepper and salt. Bake at 400° for 30 minutes or until a thermometer inserted in the meaty part of thighs registers 165°. Let stand 10 minutes.