It is very difficult to remove stains from silk clothing plus the danger of ruining the silk necktie is great. You can try out your dry cleaner and ask him if he can fix it up for sure. Also,if you are trying to find a home remedy, try using baby talcum powder. Apply it to the effected area, keep a piece of newspaper on it and then iron from above. The newspaper will soak the sauce off.
Try lightly scrubbing it with club soda.
Did you try washing it? The tag on it should say how to wash it.