Peter's Canyon Trail ends at Portola Parkway. If you cross the street to the other side of Portola Parkway, go left for a short time and it will intersect with Jamboree Road. That's the same Jamboree that starts in Newport Beach at Pacific Coast Highway. Take Jamboree up, up, till you reach East Chapman and that's where it becomes Santiago Canyon Road. Turn right on Santiago Canyon Road and you'll be on your way to Cook's Corner.

If that's too far, just turn around at Silverado Canyon Road.